JPS61285761A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To superimpose desired characters, graphics and the like on an image, by setting the potential of a signal input source in correspondence with the luminance of the graphics, characters and the like to be superimposed on the image, selectively controlling the signal input gate, and mixing the charge generated by the signal input source into the signal charge obtained from a solid-state image pickup device. CONSTITUTION:At a time point when signal charge is transferred to a floating diffused region 21, a signal input gate 25 is turned ON. Electric charge from a signal input source 26 is mixed to the signal charge accumulated in the floating diffused region 21. ON and OFF of the signal input gate 25 are controlled by the output of a timing-signal generating circuit 27, which generates a desired timing signal SIG based on the output of a CCD driving circuit 29. When the signal charge of a region, in which characters, graphics and the like are superimposed, is transferred to the floating diffused region 21, the gate 25 is turned ON. A specified potential Vs is applied to the signal input source 26 based on the output of an amplitude adjusting circuit 28, which sets a signal level (luminance) for superimposing based on the output of the CCD driving circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a solid-state imaging device, and is particularly used in a device that imprints a signal such as a character 9 figure on an image signal within an element.

[Technical background of the invention and its problems]

Generally, when imprinting characters, figures, etc. on a video signal,
An imprint signal from a subsequent circuit is mixed with the output signal of the sensor. - As an example, Section 7 describes the imprinting method used in NTaC color television cameras.
0 The sensor element 11 in FIG. 7 will be explained with reference to the drawings.
The video signal obtained is separated into R (red), G (green), and B (blue) by the color separation circuit 12.

Based on these R, G, and B signals,
A luminance signal Y and a color signal C are generated by a circuit 13 including an IJTx circuit, a modulator, etc. After that, the luminance signal Y and color signal C are normally input to a color encoder 14 and converted into an NT8C signal. and sent out. Here, when trying to record a white figure on an image, first, the signal S1 from the figure signal generation circuit 15 and the luminance signal Y
are mixed in a mixing circuit 16a to generate a signal Y' that makes the luminance signal Y constant at only the graphic portion. Also, the color signal C
and the graphic signal S2 are input to the mixing circuit 16b, and a color signal C' excluding the color signal of the graphic part is generated.

Then, when an NT8C signal is generated by the color encoder 14 based on these signals Y/, c/, a white figure is imprinted on the image.

In this way, when imprinting a figure, in addition to the figure signal generation circuit 15, mixing circuits 16m and 16b corresponding to the luminance signal Y and color signal C are required. Further, when imprinting color figures, characters, etc., it is necessary not only to remove the color signal C but also to add the color signal to be imprinted, which has the drawback of complicating the circuit.

[Purpose of the invention]

This invention was made in consideration of the above circumstances,
The purpose is to provide a solid-state imaging device that can imprint desired graphics, characters, etc. onto an image with a relatively simple configuration, and can also easily imprint color graphics and characters.

[Summary of the invention]

That is, in this invention, in order to achieve the above object, a signal input gate and a signal input source are added to the output section of the solid-state imaging device, and a figure, character, etc. is added to the output section of the solid-state imaging device, and a figure, character, etc. The desired character is set according to the brightness of the image sensor, and the signal input gate is selectively controlled to mix the charge generated in the signal input source with the signal charge obtained from the solid-state imaging device. I am trying to imprint objects, shapes, etc. onto the video.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the planar configuration of a CCD imaging device equipped with a floating diffusion type amplifier, and FIG. 3 shows the potential potential in FIG. 2 above, FIG. 4 shows the sectional structure along the Y-Y' line in FIG. 1 above, and FIG. The electric potentials shown in the figure are shown respectively. In FIG. 1, 17.17.
. . are photodiodes as photoelectric conversion elements, and these photodiodes 17, 17, . . . are arranged in a matrix.

Corresponding to each column of the photodiodes J7, 1F, . . ., vertical CCDs 8.1B, . . . are provided, and the photodiodes 17.1? ,... The signal charges generated by photoelectric conversion by these vertical C
CD18,18. It will be forwarded to... Above vertical C0D
A horizontal CCD 19 is provided at one end of 78.1 B, .
19, the data is transferred in the direction of arrow B. Above horizontal CCD1
An output gate 20 is provided at the output node 9, and signal charges sequentially transferred through the horizontal CCD 19 are accumulated in a floating diffusion region 21 via this output gate 20. The potential of this floating diffusion region 21 is then amplified by the output amplifier 22 and output as an output signal Vout.

Further, a reset gate 23 is provided adjacent to the floating diffusion region 21, and by opening this gate 23 after reading out the signal charges, the signal charges accumulated in the floating diffusion region 21 are discharged to the reset drain 24. be done. A predetermined potential vRD is applied to the reset drain 24. Further, a signal input gate 25 is provided adjacent to the floating diffusion region 21', and a signal input source 25 is provided adjacent to the floating diffusion region 21'.
The charges accumulated in the floating diffusion region 21 are mixed with the charges as a video signal transferred to and accumulated in the floating diffusion region 21. The signal input gate 25 is controlled by a timing signal 8IG outputted from a timing signal generation circuit 27, and a predetermined potential Vs set by an amplitude adjustment circuit 28 is applied to the signal input source 26. There is. The timing signal generation circuit 27 and the amplitude adjustment circuit 28 each have a vertical C0D1
B, 7 B, ... and horizontal 〇 Controlled based on the output of the CCD drive circuit 29 that drives the CD 19 0 In the above configuration, first, during normal operation (characters, figures, etc.) (when not imprinting) is shown in Figures 2 and 3.
This will be explained with reference to the figures. so, so,・ in Figure 2
... are transfer electrodes, and these transfer electrodes 30, 30 .・
... are selectively supplied with expanded clock signals H1 and R2. OG is a timing signal supplied to the output gate 20;
R8 indicates a reset signal supplied to the reset gate 23, respectively. As shown in FIG. 3, at time t1, the reset gate 23 is in an off state, and the potential of the floating diffusion region 21 is equal to the potential of the reset drain 24. By turning on the output gate 20 at the next time t and lowering the potential of the transfer electrode 29 to which the clock signal H1 is supplied, the signal charge 3 under the transfer electrode 29 is
1 is transferred to the floating diffusion region 2. At time t3, the voltage potential in the signal charge transfer completion state is 0. At this time, a voltage corresponding to the potential in the floating diffusion range 21 is output as a video signal via the output amplifier 22. At the timing, the reset gate 23 is turned on, the signal charge is discharged to the reset drain 24, and the potentials of the floating diffusion region 21 and the reset drain 24 become equal at time t.Then, at time t6, the reset gate 23 is turned on.
The reset is completed by setting OFF state, and the next signal charge 32 is transferred. Thereafter, a video signal is obtained by sequentially repeating the above-described operations. Note that in the above-described cycle, the signal input gate 25 remains in the off state.

Next, the operation of imprinting characters, figures, etc. will be explained with reference to FIGS. 4 and 5. The operation is the same as described above until the signal charge is transferred to the floating diffusion region 21, and the signal input gate 25 is turned on at the time when the signal charge is transferred to the floating diffusion region 21 (time ts in FIG. 3). Then, the charge of the signal input source 26 (signal to be imprinted) is mixed with the signal charge (video signal) accumulated in the floating diffusion region 21. The signal input gate 25 is controlled on/off by the output of a timing signal generation circuit 27 that generates a predetermined timing signal 8IG based on the output of the CCD drive circuit 29, and the signal charge in the area where characters, figures, etc. are imprinted is When transferred to the floating diffusion region 21, it is turned on.

The signal input source 26 also has a signal level (luminance) to be imprinted based on the output of the CCD drive circuit 29.
A predetermined potential v is determined by the output of the amplitude adjustment circuit 28 that sets
Here, at time t□ shown in FIG. 5, the signal input gate 25 is in the off state, and unless the potential of the signal input source 26 exceeds the potential of the signal input gate 25, floating 0, which does not affect the potential of the region 21. Then, when the signal input gate 25 is turned on as shown at time N t st, the charge of the signal input source 26 is mixed with the charge as a video signal.

FIG. 6 shows the timing at which the signal input gate 25 is turned on, and each gate is turned on when each pulse is at a high level. reset gate 2
3 is off and the clock signal H1 becomes low level, the video signal j 31 @ J 32 @ j Jg
m... is output.

However, when the clock signal H1 is at level 4 and the timing signal BIG supplied to the signal input gate 25 becomes high level and the signal input gate 25 is turned on, the signal charge corresponding to the video signal is transferred to the floating diffusion region 21. However, the potential of this floating diffusion region 21 is the same as that of the signal input source 2.
The amplitude of the output signal is determined by the potential Vs applied to the signal input source 26, regardless of the magnitude of the video signal amplitude. Therefore, by selectively mixing the charge from the signal input source 26 with the signal charge obtained from the photodiode at the position corresponding to the character or figure to be imprinted, the desired character or figure can be imprinted. .

In addition, in a single-chip solid-state imaging device in which a color filter is formed on the photodiode, if the signal input gate is turned on only when a video signal of the desired color is output, color characters and figures can be displayed. etc. can be easily imprinted. Furthermore, although the above embodiments have been described with respect to a two-dimensional solid-state imaging device, it goes without saying that the present invention can also be applied to a one-dimensional solid-state imaging device having a similar output section.

〔Effect of the invention〕

As explained above, according to the present invention, desired figures, characters, etc. can be imprinted on an image with a relatively simple configuration.
A solid-state imaging device that can easily imprint color figures and characters can be obtained.

[Brief explanation of drawings]

FIG. 1 is a plan view of a solid-state imaging device according to an embodiment of the present invention, FIG. 2 is a cross-sectional configuration diagram taken along the line x-x' in FIG. 1, and FIG. FIG. 4 is a cross-sectional configuration diagram taken along the Y-Y' line in FIG. 1, FIG. 5 is a diagram showing the potential potential at each time in FIG. 4, and FIG. is a timing chart of each signal in Fig. 4 above, and Fig. 7 is a diagram for explaining the conventional method of imprinting characters, figures, etc. on a video signal. ◇ 17... Photodiode (photoelectric conversion) means), 18.
19...CCD (charge transfer means), 20...output gate, 21...floating diffusion region (charge storage means), 22
... Output amplifier (charge amount detection means), 23 ... Reset gate (charge discharge means), 24 ... Reset drain, 25 ... Signal input gate (gate means), 26
...Signal input source (charge supply means). Applicant's agent Patent attorney Takeshi Suzue Onbe 1 Figure 3 rl N t/) 〇 -g 工 cr-(1)＞

Claims (1)

[Claims] a photoelectric conversion means; a charge transfer means for sequentially transferring signal charges obtained by photoelectric conversion by the photoelectric conversion means;
A charge storage means for accumulating the signal charge transferred by the charge transfer means, and a charge amount detection means for detecting the signal charge stored in the charge storage means, converting it into a voltage corresponding to the amount of charge, and obtaining an output. , a gate means provided adjacent to the charge storage means and selectively controlled to open and close at a predetermined timing in synchronization with the transfer of signal charges by the charge transfer means; and a gate means for transmitting signal charges to the charge storage means by the gate means. and a charge discharging means for discharging the signal charge accumulated in the charge accumulating means after detecting the amount of signal charge by the charge amount detecting means. solid-state imaging device.