JP5770958B1 - Image acquisition apparatus and imaging apparatus - Google Patents

Abstract

An object of the present invention is to enable flexible observation by increasing the degree of freedom of scanning speed of illumination light with respect to an observation object. An image acquisition apparatus includes a light source that emits illumination light, an optical scanner that scans the illumination light with respect to a sample, an optical scanner control unit, and an image of fluorescence from the sample. The detection optical systems 15 and 17 have a light receiving surface 19c and an image pickup control unit 19b in which a plurality of pixel rows 19d for picking up an imaged fluorescent image are arranged, and a signal for each of the plurality of pixel rows 19d from the light receiving surface 19c. An image pickup device 19 capable of reading, and a calculation unit 21 that calculates a signal reading interval between adjacent pixel columns 19d based on the moving speed of the irradiated region on the light receiving surface 19c by the scanning of the optical scanner 7. The imaging control unit 19b controls the signal readout of each pixel column 19d based on the calculated signal readout interval. [Selection] Figure 1

Description

  The present invention relates to an image acquisition device and an imaging device that acquire an image of an observation object.

  Recently, a CMOS (Complementary Metal Oxide Semiconductor) camera has been used to observe light from an object. In general, a CMOS camera has advantages such as faster reading speed and easier partial reading compared to a CCD (Charge Coupled Device) camera.

  Non-Patent Document 1 and Patent Document 1 below disclose that a CMOS sensor is used as an image sensor in a light sheet fluorescence microscope apparatus (Light Sheet Microscopy system). In this microscope apparatus, the observation object is imaged while scanning the excitation beam with respect to the observation object, and the scanning of the excitation beam is synchronized with the operation of the rolling shutter of the CMOS sensor.

International Publication WO2011 / 120629 Pamphlet

Eugen Baumgart and Ulrich Kubitscheck, “Scanned light sheet microscopy with confocal slit detection”, OPTICS EXPRESS, September 3, 2012, Vol. 20, no. 19, p. 21805-21814

  However, in the conventional microscope apparatus described above, since the scanning of the excitation beam is synchronized with the operation of the rolling shutter of the CMOS sensor, it is difficult to provide flexibility in the scanning speed of the excitation light. As a result, there was a tendency that flexible observation of various observation objects under various conditions was not possible.

  Therefore, the present embodiment has been made in view of such problems, and provides an image acquisition apparatus and an imaging apparatus that enable flexible observation by increasing the degree of freedom of the scanning speed of illumination light with respect to an observation target. For the purpose.

  In order to solve the above-described problem, an imaging apparatus according to an aspect of the present invention is an imaging apparatus capable of signal readout by rolling readout for each of a plurality of pixel columns, and a light receiving unit in which the plurality of pixel columns are arranged; And an imaging control unit that controls signal readout of the light receiving unit based on the drive clock. The imaging control unit defines the signal readout period of the drive clock in order to control the signal readout period of each of the plurality of pixel columns. The number of drive clocks that count the number of drive clocks to be controlled and the number of drive clocks that define the signal readout period can be variably adjusted.

  Alternatively, an image acquisition apparatus according to another aspect of the present invention is an image acquisition apparatus that acquires an image of an object by scanning the object with irradiation light, and scans the object with irradiation light. An optical scanning unit, a light receiving unit in which a plurality of pixel columns are arranged, and an imaging control unit that controls signal readout of the light receiving unit based on a driving clock, and rolling readout for each of the plurality of pixel columns from the light receiving unit An imaging device capable of signal readout, and the imaging control unit counts the drive clocks by the number of drive clocks that define the signal readout periods in order to control the signal readout periods of the plurality of pixel columns. The number of drive clocks that define the signal readout period can be variably adjusted.

  According to the present invention, flexible observation is possible by increasing the degree of freedom of the scanning speed of the illumination light with respect to the observation object.

1 is a plan view showing a schematic configuration of an image acquisition device 1 according to a preferred embodiment of the present invention. It is a side view which shows schematic structure of the image acquisition apparatus 1 of FIG. It is a figure which shows the relationship between the scanning state of the illumination light with respect to the sample S in the image acquisition apparatus 1 of FIG. 1, and the irradiated area of the fluorescence image in the image pick-up element 19a. 2 is a diagram showing a scanning state of an irradiated region R1 on the light receiving surface 19c of the imaging device 19 of FIG. 1 and exposure and signal readout timings in each pixel column 19d of the light receiving surface 19c controlled in accordance with the scanning state. is there. 3 is a timing chart showing a relationship between an exposure period and a signal readout period set for each pixel column 19d in the imaging device 19 of FIG. It is a figure which shows the to-be-irradiated area | region R1 on the light-receiving surface 19c of the imaging device 19 of FIG. 1, and the exposure area | region R2 on the light-receiving surface 19c set with respect to it by the imaging control part 19b. 6 is a timing chart showing an exposure period set for each pixel row 19d on the light receiving surface 19c when the number of stages of the exposure region R2 is controlled by the imaging control unit 19b of FIG. 6 is a timing chart showing an exposure period set for each pixel row 19d on the light receiving surface 19c when the number of stages of the exposure region R2 is controlled by the imaging control unit 19b of FIG. 6 is a timing chart showing an exposure period set for each pixel row 19d on the light receiving surface 19c when the number of stages of the exposure region R2 is controlled by the imaging control unit 19b of FIG. It is a timing chart which shows the relationship between the exposure period and signal read-out period which are set to each pixel row | line | column 19d in the imaging device 19 of the modification of this invention. It is a timing chart which shows the relationship between the exposure period and signal read-out period which are set to each pixel row | line | column 19d in the imaging device 19 of the modification of this invention. It is a timing chart which shows the relationship between the exposure period and signal read-out period which are set to each pixel row | line | column 19d in the imaging device 19 of the modification of this invention.

  Embodiments of an image acquisition device and an imaging device according to the present invention will be described below in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Each drawing is made for the purpose of explanation, and is drawn so as to particularly emphasize the target portion of the explanation. Therefore, the dimensional ratio of each member in the drawings does not necessarily match the actual one.

  FIG. 1 is a plan view schematically showing the configuration of an image acquisition device 1 according to an embodiment of the present invention, and FIG. 2 is a side view of the image acquisition device 1 of FIG. The image acquisition apparatus 1 according to the present embodiment is an apparatus for irradiating a sample (object) S with illumination light and acquiring a fluorescent image (image) generated as a result. In the following description, the direction along the optical axis of the illumination optical system of the illumination light applied to the sample S is defined as the X-axis direction, and the optical axis of the fluorescence detection optical system from the sample S perpendicular to the direction is defined as the X-axis direction. The direction along the direction is the Y-axis direction, and the direction perpendicular to the X-axis direction and the Y-axis direction is the Z-axis direction. The image acquisition device 1 is not limited to the configuration for acquiring the fluorescent image of the sample S, and may be a configuration for acquiring the reflection image, the transmission image, and the scattering image of the sample S. Various image acquisition apparatuses such as a microscope apparatus and a flow cytometer having various configurations such as a field microscope apparatus and a reflection microscope apparatus may be used.

  The image acquisition device 1 includes a light source 3 that emits illumination light having a predetermined wavelength that excites a fluorescent substance in a sample S, and an optical scanner (light scanning unit) that receives illumination light from the light source 3 via a light guide 5. 7, an optical scanner control unit (optical scanning control unit) 9 that controls the optical scanner 7, a relay optical system (irradiation optical system) 11 that guides illumination light from the optical scanner 7, and the relay optical system 11. An objective lens (irradiation optical system) 13 that condenses the illumination light toward the sample S, an objective lens (detection optical system) 15 that condenses the fluorescence from the sample S, and the fluorescence from the objective lens 15 are guided. A relay optical system (detection optical system) 17, an imaging device 19 that captures a fluorescent image from the sample S guided by the relay optical system 17, and the imaging device 19 and the optical scanner controller 9 are electrically connected. Including a calculation unit 21 It is configured. The fluorescent image picked up by the image pickup device 19 is output by output means (not shown) such as a display device connected to the image acquisition device 1.

  The light guide 5 may be configured by an optical fiber such as a single mode fiber, or may be configured by other types of optical fibers or lenses. The optical scanner 7 scans the illumination light from the light guide 5 in at least one direction (for example, one direction along the XZ plane in FIG. 2). For example, the optical scanner 7 is a galvano scanner configured by a galvanometer mirror. The optical scanner 7 scans the illumination light so that the irradiated area of the illumination light condensed in the sample S via the relay optical system 11 and the objective lens 13 is arranged in at least one direction (for example, FIG. 2). (In the Z-axis direction). Here, the illumination light applied to the sample S from the light source 3 via the light guide 5, the optical scanner 7, the relay optical system 11, and the objective lens 13 may be spot-like light or in one direction. It may be sheet-shaped light that spreads (for example, in the Y-axis direction).

  The imaging device 19 includes an imaging device 19a including a light receiving unit in which a plurality of pixel columns are arranged, and an imaging control unit 19b that controls exposure and signal readout of the imaging device 19a. This is a device capable of reading signals by rolling reading. For example, the imaging device 19 is a camera device including a CMOS image sensor, and enables exposure and signal readout by a so-called rolling shutter of the CMOS image sensor. The calculation unit 21 connected to the imaging device 19 is configured by an information processing device such as a personal computer, receives a signal related to the scanning speed of the optical scanner 7 from the optical scanner control unit 9, and based on the signal, the imaging device 19. A signal for controlling exposure and signal readout for each pixel column is generated and sent to the imaging controller 19b of the imaging device 19 (details will be described later).

  Here, with reference to FIG. 3, the relationship between the scanning state of the illumination light with respect to the sample S in the image acquisition apparatus 1 and the irradiated region of the fluorescent image in the image sensor 19a will be described. FIGS. 3A to 3D are side views showing the scanning state of the illumination light with respect to the sample S in time series, and FIGS. 3E to 3H are FIGS. 3A to 3D, respectively. The imaging state of the fluorescent image in the image sensor 19a corresponding to the scanning state of

  As shown in FIGS. 3A to 3D, the illumination light irradiated into the sample S by the scanning of the optical scanner 7 moves (scans) along one direction (Z-axis direction). Here, as shown in FIGS. 3E to 3H, the image sensor 19a is arranged so that its light receiving surface (light receiving portion) 19c is perpendicular to the optical axis (Y-axis direction) of the detection optical system. On the light receiving surface 19c, a plurality of pixel rows 19d for capturing a fluorescent image formed on the light receiving surface 19c are arranged along the Z-axis direction. With such an arrangement and configuration of the imaging device 19a, the fluorescent image of the sample S imaged on the light receiving surface 19c is irradiated in accordance with the movement of the fluorescence generation location in the sample S due to the scanning of the illumination light by the optical scanner 7. The region R1 moves (scans) along the arrangement direction (Z-axis direction) of the plurality of pixel rows 19d. The range of the irradiated region R1 can be set in various ranges. In the example of FIG. 3, the entire irradiation optical system and detection optical system are set so as to cover the four pixel columns 19d. .

  Next, with reference to FIG. 4, the exposure and signal readout operations of the imaging device 19 corresponding to the scanning of the irradiated area of the sample S will be described. 4A to 4E are side views showing the scanning state of the irradiated region R1 on the light receiving surface 19c of the imaging device 19 in time series, and FIGS. 4F to 4J are respectively shown in FIG. 5 is a timing chart showing the timing of exposure and signal readout in each pixel column 19d of the light receiving surface 19c controlled corresponding to the scanning states of FIGS. 4 (a) to (e).

  As shown in FIGS. 4A to 4E, the scanning speed SP0 of the optical scanner 7 is controlled by the optical scanner controller 9 so that the moving speed on the light receiving surface 19c becomes a predetermined speed SP1. Such a relationship between the scanning speed SP0 and the moving speed SP1 is a parameter determined by the configuration of the optical scanner 7, the configuration of the irradiation optical system including the relay optical system 11 and the objective lens 13, and the objective lens 15 and the relay optical system 17. And a parameter determined by a detection optical system including

  Corresponding to the scanning state of the irradiated region R1, the imaging control unit 19b controls the timing of exposure and signal readout in each pixel row 19d. Specifically, for each pixel column 19d, the imaging control unit 19b sets a signal readout period for reading out the charge signal immediately after the exposure period, which is a period for exposing the fluorescent image and accumulating the charge signal, Control is performed so that a period including the exposure period and the signal readout period is repeated at a predetermined cycle. The length of the exposure period and the signal readout period, their start timing, and end timing are set based on an internally generated drive clock.

  More specifically, the imaging control unit 19b generates a reset signal RST at a timing in which a certain pixel row 19dn (n is an arbitrary natural number) is synchronized with a drive clock that enters the irradiated region R1 according to the scanning of the optical scanner 7. Then, the charge in the pixel row 19dn is discharged and the exposure process is started (FIGS. 4A and 4F). Thereafter, the imaging control unit 19b generates the reset signal RST so as to start the exposure period of the pixel row 19d (n + 1) adjacent in the scanning direction by a predetermined period by counting the drive clock (FIG. 4B). ), (G)). As described above, the exposure of all the pixel rows 19d on the light receiving surface 19c is sequentially started by shifting the pixel rows 19d adjacent in the scanning direction by a predetermined period.

  In addition, the imaging control unit 19b generates a read start signal S1 at a timing when the exposure period of the pixel column 19dn is continued for a predetermined period T1n by counting the drive clock, thereby reading the charge signal of the pixel column 19dn. Is controlled to start (FIGS. 4C and 4H). That is, the charge signal accumulated in the pixel column 19dn is converted into a voltage and read. Furthermore, the imaging control unit 19b generates the readout end signal S2 at a timing at which the signal readout period of the pixel column 19dn is continued for a predetermined period T2n by counting the drive clock, thereby generating the charge signal of the pixel column 19dn. Control is performed so as to terminate the reading (FIGS. 4D and 4I).

  Similarly, the imaging control unit 19b sets a signal readout period T2 (n + 1) for the pixel column 19d (n + 1) adjacent to the pixel column 19dn. In signal readout by rolling readout in the imaging device 19, it is necessary to change the readout timing for each pixel column 19d, and in order to make the exposure period for each pixel column 19d the same, it is necessary to shift the exposure start timing for each pixel column. There is. In the example of FIG. 4, the imaging control unit 19b sets the generation timing of the readout start signal S1 between the adjacent pixel columns 19d so as to leave a predetermined interval ΔT1, thereby starting the signal readout between the adjacent pixel columns 19d. The timing is shifted by a predetermined interval ΔT1.

  Here, the shift (interval) ΔT1 of the signal readout start timing set by the imaging control unit 19b is made variable by a control signal sent from the calculation unit 21 to the imaging control unit 19b. Specifically, the calculation unit 21 acquires information related to the scanning speed SP0 of the optical scanner 7 from the optical scanner control unit 9, and determines the parameters determined by the scanning speed SP0, the magnification of the irradiation optical system, the magnification of the detection optical system, and the like. Based on the determined parameters, the moving speed SP1 of the irradiated region R1 on the light receiving surface 19c is calculated. Further, the calculating unit 21 performs exposure so that the pixel rows 19d that enter the irradiated region R1 are sequentially exposed in synchronization with the movement of the irradiated region R1 on the light receiving surface 19c based on the calculated moving speed SP1. The interval between the start timings of the periods is calculated, and accordingly, the interval ΔT1 ′ of the signal read start timing between the adjacent pixel columns 19d is determined as the signal read interval between the adjacent pixel columns 19d. Then, the calculation unit 21 sends the calculated signal read start timing interval ΔT1 'to the external signal reception unit 19e of the imaging device 19 as an external signal. The received signal read start timing interval ΔT1 'is sent as data to the imaging control unit 19b. Accordingly, the imaging control unit 19b controls the signal readout start timing of each pixel column, for example, the signal readout start timing of each pixel column, based on the signal readout start timing interval ΔT1 ′ set by the calculation unit 21. . Note that the imaging device 19 may include the calculation unit 21. In that case, the external signal receiving unit 19e of the imaging device 19 receives data such as parameters determined by the scanning speed SP0, the magnification of the irradiation optical system, and the parameters determined by the magnification of the detection optical system, etc., as external signals. Further, the external signal is not limited to these as long as it is data and parameters for setting the interval ΔT1 ′ of the signal read start timing.

  Next, with reference to FIG. 5, the adjustment operation of the interval ΔT1 of the signal readout start timing by the imaging control unit 19b will be described in more detail. FIG. 5 is a timing chart showing the relationship between the exposure period and the signal readout period set for each pixel column 19d in the imaging device 19.

  FIG. 5A is a timing chart showing the relationship between the exposure period and the signal readout period in normal rolling readout. In the case of normal rolling readout, the signal readout period T2 is set to the time required for signal readout, and the interval ΔT1 of the signal readout start timing is set to be the signal readout period T2. Therefore, the imaging control unit 19b counts the drive clock CLK repeated at a predetermined cycle T0 from the read start signal S1 for the previous pixel column 19d by a number corresponding to the signal read start timing interval ΔT1. A read start signal S1 is generated for the next pixel column 19d. In contrast, in FIG. 5B, in order to set the signal readout start timing interval ΔT1 to the set signal readout start timing interval ΔT1 ′, the signal readout period T2 corresponding to the time required for signal readout is set. Is followed by a variable delay period T3. Specifically, in FIG. 5B, the imaging control unit 19b calculates the delay time T3 from the signal readout start timing interval ΔT1 ′ and the signal readout period T2, and corresponds to the signal readout period T2 in the drive clock CLK. The drive clock is adjusted so as to provide the delay period T3 at the timing after the previous drive clock CLK reaching the number of clocks (immediately before the generation of the read start signal S1). At this time, since the imaging control unit 19b does not generate a driving clock in the delay period T3, the imaging control unit 19b counts the number of driving clocks CLK equal to the number of driving clocks CLK corresponding to ΔT1 in FIG. The readout start signal S1 is generated for the pixel column 19d of the next column. As a result, the interval of the signal readout start timing between the adjacent pixel columns 19d is set to time ΔT1 ′ = T2 + T3. In this way, the imaging control unit 19b can variably control the signal readout start timing of each pixel column in accordance with the signal readout start timing interval ΔT1 ′ calculated by the calculation unit 21. It is. Note that the timing for providing the delay period T3 is not limited to the timing immediately before the generation of the read start signal S1, but may be provided during the signal read period T2.

  Further, the imaging control unit 19b is configured to be able to variably set the number of pixel columns in the exposure region on the light receiving surface 19c to be exposed simultaneously by adjusting the exposure period for each pixel column 19d. FIG. 6 shows an illuminated region R1 on the light receiving surface 19c of the imaging device 19 and an exposure region R2 on the light receiving surface 19c set by the imaging control unit 19b. In general, it is optically difficult to make the fluorescence from the sample S incident on the light receiving surface 19c into a slit shape. Therefore, by setting the range (number of steps) of the exposure region R2 including the pixel column 19d to be exposed at the same time by the imaging control unit 19b, it is possible to perform imaging in a state where pseudo-slit fluorescence is incident.

  Specifically, FIGS. 7 to 9 show exposure periods set for each pixel row 19d on the light receiving surface 19c when the number of exposure regions R2 is controlled by the imaging control unit 19b. . In each figure, (a) shows an exposure region R2 set on the light receiving surface 19c, and (b) shows each pixel set corresponding to the exposure region R2 shown in (a). An exposure period T1 and a signal readout period T2 in column 19d are shown. In each of the exposure period T1 and the signal readout period T2 set in each, the interval of the respective start timings between the adjacent pixel columns 19d is based on the calculation result of the calculation unit 21, and the irradiation region R1 on the light receiving surface 19c. Set to synchronize with movement.

  As shown in FIG. 7, when the exposure area R2 is set to four stages, the length of the exposure period T1 is set by the imaging control unit 19b so that the number of stages of the pixel column 19d in which the exposure periods T1 overlap is four. Is set. That is, the calculation unit 21 acquires information related to the scanning speed SP0 of the optical scanner 7 from the optical scanner control unit 9, and the movement speed SP1 of the irradiated region R1 on the light receiving surface 19c calculated based on the scanning speed SP0, the light receiving surface. Based on the width W1 (FIG. 6) of the pixel column 19d in the scanning direction (rolling readout direction) 19c and the number of stages of the pixel column 19d in the exposure region R2 to be set, the length T1 of the exposure period set for each pixel column 19d Is calculated. Furthermore, the calculation unit 21 sends the calculated exposure period length T1 to the external signal reception unit 19e of the imaging device 19 as an external signal. The received external signal is sent to the imaging control unit 19b. Accordingly, the length T1 of the exposure period is variably adjusted by the imaging control unit 19b. For example, the length T1 of the exposure period is changed by changing the number of drive clocks that define the length of the exposure period in the imaging control unit 19b. The calculation unit 21 is configured so that the number of stages of the pixel column 19d in the exposure region R2 that determines the length T1 of the exposure period can be variably set. As described above, the exposure region R2 is set in a plurality of stages, thereby improving the sensitivity of capturing the fluorescent image.

  Similarly, as shown in FIG. 8, when the exposure region R2 is set to one stage, the imaging control unit 19b sets the exposure period T1 of the adjacent pixel column 19d based on the calculation result of the calculation unit 21. The length of the exposure period T1 is set so as not to overlap. In this way, by setting the exposure area R2 to a relatively small number of stages such as one, the spatial resolution of fluorescent image capturing is improved.

  Further, as shown in FIG. 9, the exposure region R2 is set to one stage, and based on the calculation result of the calculation unit 21, the imaging control unit 19b performs exposure so that the exposure periods T1 of the adjacent pixel columns 19d do not overlap. The length of the period T1 is set. At this time, since the moving speed SP1 of the irradiated region R1 is set slower than that in FIG. 8, the lengths of the exposure period T1 and the signal readout period T2 are set to be relatively long. As described above, the exposure region R2 is set with a relatively small number of stages, so that the spatial resolution of fluorescent image capturing is improved, and the exposure time of each pixel row 19d is longer than in the case of FIGS. Therefore, the sensitivity is improved. On the other hand, in the case of FIGS. 7 and 8, the time resolution is excellent because the scanning speed is higher than that in FIG.

  Furthermore, it is possible to set the number of pixels from which a signal is read out of a plurality of pixels constituting the pixel row 19d, and use the number of pixels as a parameter for calculating the exposure period T1. In this case, when it is not necessary to read out the entire pixel column 19d, only the necessary pixels can be read out. In addition, it is possible to set the signal readout period T2 to be short, and it is possible to give more flexibility to the setting of the signal readout start timing interval ΔT1.

  In a general microscope apparatus, it has been optically difficult to make light from an object incident on a light receiving surface of a CMOS sensor into a slit shape.

  Therefore, in view of such a problem, the present embodiment has an object to make it possible to easily capture light from an observation object as a slit-like image.

  According to the image acquisition device 1 described above, the illumination light emitted from the light source 3 is scanned with respect to the sample S by the optical scanner 7, and the fluorescence emitted from the sample S is imaged via the detection optical system accordingly. Imaged by device 19. At that time, based on the moving speed of the irradiated region R1 on the light receiving surface 19c of the imaging device 19 by scanning of the illumination light, the interval of the signal reading start timing between the adjacent pixel rows 19d on the light receiving surface 19c is calculated, Based on the calculation result, the signal readout start timing of each pixel column 19d is controlled. As a result, even if the scanning speed of the illumination light is changed, the signal readout timing in the image sensor can be optimized accordingly, so that the flexible scanning of the sample S can be performed by giving the scanning speed of the illumination light to the sample S flexible. Is realized. Further, by performing exposure of the necessary pixel columns only while the fluorescence is irradiated, it is possible to improve the spatial resolution by reducing the influence of background noise such as scattered light in the image of the entire optical scanning range of the sample S. it can.

  Here, in the imaging device 19, the signal read start timing is controlled based on the drive clock, and the interval between the signal read start timings is adjusted by providing a delay period in the drive clock. Thereby, the signal read start timing of each pixel column 19d can be set easily and reliably without being limited to the upper limit of the counter for counting the drive clock. Further, it is possible to finely set the interval of the signal readout start timing of each pixel column 19d. Furthermore, since the frequency of the drive clock is maintained, the rolling read timing optimization process by changing the frequency becomes unnecessary.

  In addition, by setting the exposure period of each pixel row 19d by the light receiving surface 19c, the number of exposure regions R2 on the light receiving surface 19c can be set as necessary. In addition, time resolution and imaging sensitivity can be adjusted as appropriate.

  In addition, among the plurality of pixels constituting each pixel column 19d, the number of pixels from which signals are read can be set variably. As a result, the signal readout period T2 can be adjusted, and a further degree of freedom can be given to the setting of the signal readout start timing interval ΔT1.

  In addition, this invention is not limited to embodiment mentioned above. For example, other adjustment methods may be employed as the adjustment method of the signal readout start timing interval ΔT1 by the imaging control unit 19b.

  FIG. 10 is a timing chart showing the relationship between the exposure period and the signal readout period set for each pixel column 19d in the imaging device 19 according to the modification of the present invention. In the case shown in the drawing, the imaging control unit 19b sets the interval ΔT1 of the signal readout start timing of the adjacent pixel column 19d by adjusting the number of drive clocks that define the signal readout period T2 of each pixel column. . That is, the imaging control unit 19b corresponds to the signal readout start timing interval ΔT1 ′ calculated based on the signal readout start timing interval ΔT1 ′ calculated by the calculation unit 21 and the frequency 1 / T0 of the drive clock CLK. The number of drive clocks CLK is calculated, and the number of drive clocks is adjusted as the number of clocks corresponding to the signal readout period T2a. Therefore, the imaging control unit 19b counts the drive clock CLK repeated at a predetermined period T0 from the readout start signal S1 for the previous pixel column 19d by a number corresponding to the signal readout start timing interval ΔT1 ′, thereby adjacent to the adjacent pixel row 19d. A read start signal S1 for the next pixel column 19d to be generated is generated. In this way, the imaging control unit 19b can variably control the signal readout start timing of each pixel column in accordance with the signal readout start timing interval ΔT1 calculated by the calculation unit 21. is there. In this case, the signal readout start timing of each pixel column 19d can be set easily and reliably. Further, even if the drive clock is supplied at the timing when the signal readout of each pixel column 19d is completed, empty readout is performed, so that the signal readout processing is not affected. Furthermore, since the frequency of the drive clock is maintained, the rolling read timing optimization process by changing the frequency becomes unnecessary.

  Furthermore, FIG. 11 is a timing chart showing the relationship between the exposure period and the signal readout period set for each pixel column 19d in the imaging device 19 of another modification of the present invention. In the case shown in the figure, the imaging control unit 19b sets the signal readout start timing of each pixel column 19d by adjusting the frequency of the drive clock that defines the signal readout period T2 of each pixel column. That is, based on the signal readout start timing interval ΔT1 ′ calculated by the calculation unit 21 and the number of clocks that define the signal readout period T2, the frequency of the drive clock is changed to a frequency corresponding to the signal readout period T2b. The frequency 1 / T0a is calculated, and the frequency of the drive clock CLK is adjusted to the calculated frequency 1 / T0a. Accordingly, the imaging control unit 19b counts the drive clock CLK repeated at a predetermined cycle T0a from the readout start signal S1 for the previous pixel column 19d by a number corresponding to the signal readout start timing interval ΔT1 ′. A read start signal S1 for the next pixel column 19d to be generated is generated. In this way, the imaging control unit 19b can variably control the signal readout start timing of each pixel column according to the interval ΔT1 of the signal readout start timing calculated by the calculation unit 21. is there. In this case, the signal readout start timing of each pixel column 19d can be set easily and reliably without being limited to the upper limit of the counter for counting the drive clock.

  FIG. 12 is a timing chart showing the relationship between the exposure period and the signal readout period set for each pixel column 19d in the imaging device 19 according to another modification of the present invention. In the case shown in the figure, the imaging control unit 19b drives the interval ΔT2 between the signal readout end timing of the previous pixel column 19d and the signal readout start timing of the next pixel column to define the interval ΔT2. Set by adjusting the number of clocks. That is, the interval ΔT2 is calculated based on the signal reading start timing interval ΔT1 ′ calculated by the calculation unit 21, the signal reading period T2, and the frequency 1 / T0 of the drive clock CLK. Specifically, the imaging control unit 19b first counts the drive clock CLK repeated at a predetermined cycle T0 from the read start signal S1 for the previous pixel column 19d by a number corresponding to the signal read period T2, thereby reading the read end signal. S2 is generated. Then, the number of clocks corresponding to the interval ΔT2 is counted from the read end signal S2, and a read start signal S1 for the next adjacent pixel column 19d is generated. That is, since the imaging control unit 19b counts the number of clocks corresponding to the period T2c obtained by adding the signal readout period T2 and the interval ΔT2, the signal readout start timing calculated by the calculation unit 21 is set to the signal readout start timing of each pixel column. It is possible to variably control according to the start timing interval ΔT1. In this case, since the frequency of the drive clock is maintained, the rolling read timing optimization process by changing the frequency becomes unnecessary.

  Note that the method for setting the interval of the signal readout start timings shown in FIGS. 5 and 10 to 12 may be appropriately combined. Also, the setting method shown in FIGS. 5 and 10 to 12 may be selected according to the signal read start timing interval ΔT1 ′.

  The imaging control unit 19b may include an image sensor. In the above-described embodiment, the signal readout start timing interval is calculated (set) as the signal readout interval, and the imaging control unit 19b controls the signal readout start timing of each pixel column. For example, the interval of signal reading end timing may be calculated (set), and the signal reading end timing of each pixel column may be controlled.

  Here, in the imaging apparatus, it is preferable that signal readout is controlled based on the drive clock, and the imaging control unit adjusts the drive clock based on the calculated signal readout interval. By adopting such a configuration, it is possible to easily and reliably set the signal readout interval of each pixel column of the imaging device.

  It is also preferable that the imaging control unit adjusts the drive clock by providing a delay period. In this case, the signal readout interval of each pixel column of the imaging device can be set finely.

  Furthermore, it is also preferable that the imaging control unit sets the delay period before signal readout. In this way, it is possible to easily set a signal readout shift between the pixel columns.

  Furthermore, it is also preferable that the imaging control unit adjusts the drive clock by changing the frequency of the drive clock. In this way, the signal readout interval of each pixel column can be set easily.

  The image pickup apparatus controls signal readout based on the drive clock, and the image pickup control unit adjusts the number of drive clocks that define the signal read based on the calculated signal readout interval and the drive clock frequency. Is preferred. By adopting such a configuration, it is possible to easily and reliably set the signal readout interval of each pixel column of the imaging device.

  Furthermore, it is also preferable that the imaging control unit adjusts the number of drive clocks that define the signal readout interval. In this way, it is possible to easily set a signal readout shift between the pixel columns.

  Furthermore, it is also preferable that the imaging control unit adjusts the number of drive clocks that define a signal readout period. In this way, it is possible to easily set a signal readout shift between the pixel columns.

  Further, it is preferable that the calculation unit sets the exposure period by the light receiving unit based on the moving speed of the irradiated region, the width of the pixel column, and the number of stages of the pixel column corresponding to the irradiated region. By adopting such a configuration, the number of pixel columns that can be exposed simultaneously can be set as necessary, so that the spatial resolution and temporal resolution can be appropriately adjusted.

  Furthermore, it is also preferable that the number of pixel columns corresponding to the irradiated region is set variably. In this case, the spatial resolution can be adjusted freely.

  Furthermore, it is also preferable that the imaging control unit variably sets the number of pixels from which signals are read out among a plurality of pixels constituting each pixel column. In this case, it is easy to adjust the signal readout period, and it is possible to give more flexibility to the setting of the signal readout interval.

  Alternatively, the imaging apparatus of the present invention is an imaging apparatus that can perform signal readout by rolling readout for each of a plurality of pixel columns, and an imaging that controls signal readout of the light receiving unit in which the plurality of pixel columns are arranged. And an imaging control unit configured to control signal readout based on a drive clock and variably set signal readout intervals between adjacent pixel columns.

  According to such an imaging apparatus, the signal readout interval between adjacent pixel columns of the light receiving unit is changed based on the drive clock. Thereby, flexible observation of the object can be realized by giving a degree of freedom to the signal reading shift of each pixel column of the image signal of the object to be observed.

  Here, it is preferable that the signal readout interval between adjacent pixel columns is set based on the moving speed of the irradiated region on the light receiving unit. By so doing, it is possible to improve the spatial resolution by reducing the influence of background noise such as scattered light in the image of the entire optical scanning range of the object.

  In addition, it is preferable that the imaging control unit adjusts the drive clock based on a signal readout interval calculated based on the moving speed of the irradiated region on the light receiving unit. By adopting such a configuration, it is possible to easily and reliably set the signal readout interval of each pixel column of the imaging device.

  It is also preferable that the imaging control unit adjusts the drive clock by providing a delay period. In this case, the signal readout interval of each pixel column of the imaging device can be set finely.

  Furthermore, it is also preferable that the imaging control unit sets the delay period before signal readout. In this way, it is possible to easily set a signal readout shift between the pixel columns.

  Furthermore, it is also preferable that the imaging control unit adjusts the drive clock by changing the frequency of the drive clock. In this way, the signal readout interval of each pixel column can be set easily.

  In addition, the imaging control unit may adjust the number of drive clocks that define the signal readout based on the signal readout interval and the drive clock frequency calculated based on the moving speed of the irradiated region on the light receiving unit. Is preferred. By adopting such a configuration, it is possible to easily and reliably set the signal readout interval of each pixel column of the imaging device.

  Furthermore, it is also preferable that the imaging control unit adjusts the number of drive clocks that define the signal readout interval. In this way, it is possible to easily set a signal readout shift between the pixel columns.

  Furthermore, it is also preferable that the imaging control unit adjusts the number of drive clocks that define a signal readout period. In this way, it is possible to easily set a signal readout shift between the pixel columns.

  Further, it is preferable that the exposure period by the light receiving unit is set based on the moving speed of the irradiated region, the width of the pixel row, and the number of stages of the pixel row corresponding to the irradiated region. By adopting such a configuration, the number of pixel columns that can be exposed simultaneously can be set as necessary, so that the spatial resolution and temporal resolution can be appropriately adjusted.

  Furthermore, it is also preferable that the number of pixel columns corresponding to the irradiated region is set variably. In this case, the spatial resolution can be adjusted freely.

  It is also preferable that an external signal receiving unit for receiving an external signal is further provided, and the signal readout interval between adjacent pixel columns is set based on the external signal. By adopting such a configuration, it is possible to easily set the signal readout interval of each pixel column of the image signal of the observation object, and to realize flexible observation of the object.

  In addition, it is also preferable that the imaging control unit variably sets the number of pixels from which signals are read out among a plurality of pixels constituting each of the pixel columns. In this case, it is easy to adjust the signal readout period, and it is possible to give more flexibility to the setting of the signal readout interval.

  DESCRIPTION OF SYMBOLS 1 ... Image acquisition device, 3 ... Light source, 7 ... Optical scanner (optical scanning part), 9 ... Optical scanner control part (optical scanning control part), 15 ... Objective lens (detection optical system), 17 ... Relay optical system (detection) Optical system), 19 ... Imaging device, 19b ... Imaging control unit, 19c ... Light receiving surface (light receiving unit), 19d ... Pixel array, 19e ... External signal receiving unit, 21 ... Calculation unit, S ... Sample (object).

Claims (8)

An imaging device capable of signal readout by rolling readout for each of a plurality of pixel columns,
A light receiving unit in which a plurality of pixel columns are arranged;
An imaging control unit that controls signal readout of the light receiving unit based on a driving clock;
The imaging control unit counts the driving clock by the number of driving clocks that define the signal reading period in order to control the signal reading period of each of the plurality of pixel columns, and each of the plurality of pixel columns. In order to control the exposure period, the light receiving unit that is simultaneously exposed by counting the drive clock by the number of drive clocks defining the exposure period and changing the number of drive clocks defining the exposure period The number of stages of the pixel column is set to be variable,
The number of drive clocks defining the signal readout period and the number of drive clocks defining the exposure period are variably adjustable.
Imaging device.   The number of drive clocks defining the exposure period is set based on at least the number of stages of the pixel columns of the light receiving unit that are exposed simultaneously.
The imaging device according to claim 1. The number of drive clocks that define the signal readout period is set so that the movement of the irradiated region, which is the light irradiation region of the object imaged on the light receiving unit, and the signal readout by the rolling readout are synchronized. The
The imaging device according to claim 1 or 2 . An external signal receiver for receiving external signals;
The imaging control unit controls signal readout of the light receiving unit based on the external signal.
The imaging device according to any one of claims 1 to 3 . An image acquisition device for acquiring an image of the object by scanning irradiation light with respect to the object,
An optical scanning unit that scans the object with the irradiation light;
A light receiving unit in which a plurality of pixel columns are arranged, and an imaging control unit that controls signal reading of the light receiving unit based on a drive clock, and signal reading by rolling reading for each of the plurality of pixel columns from the light receiving unit. An imaging device capable of
The imaging control unit counts the driving clock by the number of driving clocks that define the signal reading period in order to control the signal reading period of each of the plurality of pixel columns, and each of the plurality of pixel columns. In order to control the exposure period, the light receiving unit that is simultaneously exposed by counting the drive clock by the number of drive clocks defining the exposure period and changing the number of drive clocks defining the exposure period The number of stages of the pixel column is set to be variable,
The number of drive clocks defining the signal readout period and the number of drive clocks defining the exposure period are variably adjustable.
Image acquisition device.   The number of drive clocks defining the exposure period is set based on at least the number of stages of the pixel columns of the light receiving unit that are exposed simultaneously.
The image acquisition apparatus according to claim 5. The number of drive clocks defining the signal readout period is set so that the movement of the irradiated region on the light receiving unit by the optical scanning unit and the signal readout by the rolling readout are synchronized.
The image acquisition device according to claim 5 or 6. The imaging apparatus further includes an external signal receiving unit that receives an external signal,
The imaging control unit controls signal readout of the light receiving unit based on the external signal.
Image acquisition device according to any one of claims 5-7.

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