JP2009026220A - Vascular image input apparatus and vascular image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a new compact vascular image input apparatus, which easily inputs a vein image as an image. <P>SOLUTION: The vascular image input apparatus is provided with; a lens array 10, a light receiving means 20 with minute light receiving regions PS one-to-one corresponding to each convex lens L on a light receiving surface 31, a light shielding means 30 with holes forming non-reflective light guide between the convex lens L and the minute light receiving region PS corresponding to it according to the arrangement of the convex lens L and isolating visual field region for each respective convex lens L for each minute light receiving region, and illuminating means 41 and 42 illuminating a vein part 01 to be captured as the input image. In addition, a positioning position 11 is formed for positioning a human body surface which is close to the vein part 01, near-infrared light from the surface including the vein part 01 is transmitted to the minute light receiving region PS corresponding to each convex lens L, and image information is composed for the vein part 01 using the light receiving amount for each minute light receiving region as one picture element information. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a blood vessel image input device and a blood vessel image reading device.

  In connection with ATMs (automatic transaction devices) of financial institutions, biometric authentication is being put into practical use as a means for identity verification. Biometric authentication uses physical differences between individuals, and fingerprints, vein patterns, iris patterns, and the like that are unique to each individual are often detected. In particular, the vein pattern of the palm or finger can be detected simply by placing the palm or finger on the detection device, and is becoming widespread because of its easy detection operation.

  As a method for detecting a vein pattern, Patent Document 1 discloses a method of fluoroscopically capturing a three-dimensional image of a finger vein pattern. Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique for automatically adjusting an imaging focus with respect to a vein pattern as a subject.

  The methods disclosed in Patent Documents 1 and 2 each have a problem of highly accurate detection of a vein pattern, and the apparatus tends to be complicated and expensive. In the device disclosed in Patent Document 2, an image to be detected is formed on an image pickup means by a single lens system, so that the optical distance from the subject to the image pickup surface is long and it is difficult to reduce the size of the apparatus.

  On the other hand, as the accuracy required for detecting the vein pattern, for example, it is almost sufficient to be able to read “a vein with a thickness of about 1 mm at a position of about 1 mm from the finger surface”. In some cases, simpler detection is required.

JP2007-115072 JP2007-115072

  In view of the circumstances described above, an object of the present invention is to realize a novel blood vessel image input device and blood vessel image reading device that can be configured in a small size and can easily input a vein image as image information.

The blood vessel image input device of the present invention is a “blood vessel image input device for vein authentication”.
That is, it is a device that inputs a blood vessel image (vein image) as image information in order to identify an individual by a vein pattern.
A blood vessel image input apparatus according to a first aspect includes a lens array, a light receiving means, a light shielding means, and an illumination means, and a positioning portion is formed.

The “lens array” has a parallel plate shape and is formed by arraying minute convex lenses at an array density of 200 dpi to 500 dpi.
The “light receiving means” has a minute light receiving area corresponding to 1: 1 on each convex lens of the lens array on the light receiving surface. The light receiving surface is a flat surface.

The “light-shielding means” is disposed between the lens array and the light-receiving means, and “a hole forming a non-reflective light guide path between each convex lens of the lens array and the corresponding minute light-receiving area” is provided in the lens array. Are formed corresponding to the arrangement of the convex lenses, and “a visual field region for each convex lens is independent for each minute light receiving region” in the lens array.
The “illuminating means” illuminates a vein portion to be captured as an image with near infrared light. Therefore, it is necessary that the light shielding means is at least “light shielding against near infrared light emitted by the illumination means”.

The “positioning portion” is a portion that is formed at a predetermined proximity position from the lens surface array in the lens array and positions the human body surface close to the vein portion to be authenticated.
Near-infrared light from the “surface including the vein portion” inside the human body surface positioned by the positioning unit is transmitted to the corresponding minute light receiving region by the individual convex lenses of the lens array. The amount of light received for each minute light receiving region of the light receiving means constitutes “image information of the vein portion to be authenticated as one pixel information”.

  Supplementing a little, the arrangement pitch of the convex lenses in the lens array is 200 dpi to 500 dpi as described above. 200 dpi is 0.125 mm in the lens arrangement pitch, and the lens arrangement pitch becomes smaller as the arrangement density increases. In the blood vessel input device according to the present invention, if the lens arrangement pitch is about 200 dpi, “a vein having a thickness of about 0.1 mm” can be practically read sufficiently. The higher the array density of the lens array, the higher the resolution of the input blood vessel image, but the numerical aperture of each convex lens will be reduced, and each convex lens of the lens array will become a “dark lens” and each minute light receiving area Since the amount of light received decreases, it takes time to input a blood vessel image, which is not preferable. From such a viewpoint, the upper limit of the arrangement pitch of the convex lenses is about 500 dpi.

  The “field region” is a region corresponding to one “convex lens” corresponding to the “blood vessel state in the living body” to be detected, and the light shielding means “makes the field region independent for each minute light receiving region”. Means that only the light from the field area of the single convex lens is guided to the minute light receiving area corresponding to the single convex lens by the light shielding by the light shielding means.

  “Near-infrared light” emitted by the illumination means is light having a wavelength of about 700 to 1000 nm. Near-infrared light in this wavelength region is well absorbed by “hemoglobin in blood flowing in blood vessels (veins)”, but is well scattered by muscles, fats, bone tissues, etc. in the living body. The “contrast with other tissues” can be increased. For example, in the case of inputting a finger vein pattern as a blood vessel image, the illumination means irradiates near-infrared light by irradiating from the side of the contact surface and scattering from the inside of the finger. May be “illuminated”, or irradiation may be performed so that the finger is transmitted from the back of the finger.

  “Non-reflecting light guide” means that the peripheral wall of the hole forming it is non-reflective. That is, the hole forming the non-reflecting light guide path between each convex lens of the lens array and the minute light receiving region corresponding thereto corresponds to the light from the convex lens corresponding to the hole without being reflected by the peripheral wall of the hole. Ideally, the light is guided to a minute area, and light from another convex lens that does not correspond to the hole is absorbed by the peripheral wall of the hole and shielded against the “minute area corresponding to the hole”. In this way, “the visual field area for each convex lens is independent for each minute light receiving area”.

  The “positioning part” is a part for positioning the human body surface close to the vein part to be authenticated. As in the case of the embodiments described later, the “surface of the human body” is placed at a predetermined proximity position from the lens surface array in the lens array. However, the present invention is not limited to this. For example, around the transparent cover of the lens array, the human body surface may be positioned at a predetermined position from the lens surface array. It is also possible to provide a positioning guide portion, and the human body surface can be positioned without contact with the transparent cover surface by this guide portion.

  2. The blood vessel image input device according to claim 1, wherein each of the minute light receiving areas corresponding to 1: 1 for each convex lens of the lens array is composed of “one light receiving portion, and the output of this one light receiving portion is one pixel. (Claim 2), each of the minute light receiving areas corresponding 1: 1 to the convex lenses of the lens array may be “consisting of a plurality of light receiving parts, The output sum may constitute one pixel information ”(claim 3).

  The light receiving means in the blood vessel image input apparatus according to claim 3 is defined as “a small light receiving portion arranged uniformly at a pitch smaller than the arrangement pitch of the convex lenses in the lens array”. The “opening on the light receiving means side of each hole forming the optical path” may define an array region of the light receiving portions constituting the individual micro light receiving regions (claim 4).

  The blood vessel image input device according to any one of claims 1 to 4, wherein each convex lens of the lens array connects "an image that is less than or equal to one time the vein part in the visual field region" on or near the minute light receiving region of the light receiving means. It is preferable to form an image (claim 5).

  The “lens array” in the blood vessel image input device according to any one of claims 1 to 5 has a parallel plate shape, and one surface thereof is formed into a flat surface, and a lens array of minute convex lenses is formed on the other surface. The formed surface of the lens array is directed to the light receiving means, and the surface formed on the flat surface forms a “positioning portion for positioning the human body surface close to the vein portion to be authenticated”. (Claim 6).

  As described above, the convex lens array formed on the lens array can be “formed only on one side of the lens array”, but the two lens surfaces that function as a convex lens as a whole are applied to both sides of the flat substrate. The shaft may be shared. In such a case, for example, a “thin parallel plate separate from the lens array” is arranged on the lens surface array opposite to the light receiving means, and the surface thereof is used as a contact surface. The “surface opposite to the light receiving means” itself may be the contact surface.

  The blood vessel image input device according to any one of claims 1 to 6, wherein the “light-shielding means disposed between the lens array and the light-receiving means” has one end in the optical axis direction in contact with the lens array, and the like. The end can be brought into contact with the light receiving surface of the light receiving means to function as a spacer for maintaining a distance between the lens array and the light receiving means. The optical axis direction in the light shielding means is the optical axis direction of the convex lens corresponding to the hole forming the non-reflective light guide.

  The blood vessel image input device according to any one of claims 1 to 7, wherein the arrangement of the convex lenses in the lens array and the arrangement of the micro light receiving areas in the light receiving means are two-dimensional (of course, a non-reflective light guide in the light shielding means). However, the arrangement of the convex lenses in the lens array and the arrangement of the micro light receiving areas in the light receiving means are one-dimensional (of course in the light shielding means). (The arrangement of the holes for the non-reflective light guide is also one-dimensional.) (Claim 9).

  The blood vessel image reading device according to the present invention includes the lens array, the light receiving unit, and the light shielding unit in the blood vessel image input device according to any one of claims 1 to 9, and a predetermined proximity position from the lens surface array in the lens array. Further, a positioning part for positioning the human body surface close to the vein part to be authenticated is formed (claim 10). That is, the blood vessel image reading device is obtained by removing the illumination unit from the blood vessel image input device according to any one of claims 1 to 9 described above.

  The blood vessel image input device according to claim 11 is arranged such that a plurality of blood vessel image reading devices according to claim 10 are arranged in accordance with “a desired region of a human body surface having a vein portion to be authenticated”, and one or more regions to be read are arranged. The illumination means is configured to illuminate with near infrared light.

  As described above, in the blood vessel image input device of the present invention, near infrared light in a wavelength region that is well absorbed by hemoglobin in blood flowing in a vein is irradiated to a “human body part having a vein part to be authenticated”. The muscle, fat, and bone tissue in the body scatters near-infrared rays well. Eventually, the portion closest to the human body surface (for example, palm surface or finger surface) in contact with the contact surface (1-2 mm from the skin surface) The portion other than the vein at the position) becomes a “substantially uniform background” by scattering, and the state of the vein closest to the contact surface is the object of detection. The “state of the vein closest to the contact surface” to be detected is referred to as “test vein pattern” for convenience.

  Then, this test vein pattern is divided into field regions for each convex lens constituting the lens array, and near-infrared light from the "test vein pattern portion" for each field region thus divided is converted by the convex lens. It is guided to “a small light receiving area corresponding to this convex lens” and converted into an electric signal. At this time, since the light shielding means makes the visual field area independent for each minute light receiving area, the light from the visual field area of the single convex lens is displayed in the minute light receiving area corresponding to one convex lens by the light shielding by the light shielding means. Only light is guided. "

  In other words, the vein pattern to be examined is converted into an electrical signal with the “field region of each convex lens constituting the lens array” as one pixel. Thus, in the blood vessel image input device of the present invention, the input image is the “distribution in all the micro light receiving areas” of the light amount guided from each of the visual field areas to the corresponding micro light receiving area. . Therefore, the light guided by the individual convex lenses of the lens array does not necessarily have to be “imaged on the minute light receiving area corresponding to the convex lens”. Instead of being reflected in the image, the amount of light guided to one minute light receiving area is used as “information representing one pixel”.

  In this way, each convex lens of the lens array is not necessarily required to “form an image of the visual field region on the minute light receiving region” of the test information pattern, but as described in “5, each convex lens of the lens array”. However, if the image is formed on or near the minute light receiving region of the light receiving means, the light condensing property of the light guided to the minute light receiving region is increased. It is easy to increase the contrast of the input image. In this way, the distance between the lens array and the light receiving means can be shortened.

  As is apparent from the above description, the image information input by the blood vessel image input device of the present invention is “simplified information of the visual field area corresponding to one convex lens as one pixel information” in the lens array. Therefore, the resolution of the input image information depends on the arrangement density of the convex lenses in the lens array, but the arrangement density of the convex lenses is about 200 dpi to 500 dpi, and if the arrangement density is within this range, the resolution is practically sufficient. Image information can be configured.

  As described above, according to the present invention, a novel blood vessel image input device / blood vessel image reading device can be realized. Since the blood vessel image reading device of the present invention uses a lens array of minute convex lenses having an array density of 200 dpi to 500 dpi, the distance from the contact surface that contacts the surface of the living body to the light receiving means can be reduced, and therefore, it is thin, that is, small in size. The vein image can be easily input as image information. In addition, since the information on the field of view for one convex lens is simplified to one pixel information, unlike “when image processing is performed on images formed by individual convex lenses”, complicated image processing is not required.

Hereinafter, embodiments will be described.
FIG. 1 is a diagram for explaining one embodiment of a blood vessel image input apparatus. In this example, the finger vein pattern is the target of image input.
In FIG. 1A, reference numeral 10 denotes a lens array, reference numeral 20 denotes a light shielding means, reference numeral 30 denotes a light receiving means, reference numerals 41 and 42 denote illumination means, reference numeral 0 denotes a finger, reference numeral 01 denotes a vein to be captured as an image. "Parts (ie, vein parts to be authenticated)" are shown.

  The lens array 10 has a parallel plate shape, and is formed by two-dimensionally arranging minute convex lenses L at an appropriate arrangement density of about 200 dpi to 500 dpi. The two-dimensional arrangement of the convex lenses L is a square arrangement (an arrangement in which the convex lenses L are arranged like a grid in the directions orthogonal to each other at the same pitch). In this embodiment, the convex lens L is formed only on one surface (the lower surface in the drawing) of the parallel plate-shaped lens array 10, and the opposite surface (the upper surface in the drawing) is “the vein to be authenticated”. It is a contact surface 11 as a positioning portion for positioning by contacting the surface of the human body close to the portion 01 (the surface of the finger 0).

  The light receiving means 30 arranges the minute photosensors PS in a two-dimensional square arrangement “corresponding 1: 1 with the individual convex lenses L of the lens array 10”, and the minute sensor surface of each photosensor PS is “ It is the thing of the structure integrated so that it may be arranged on the common plane which is the light-receiving surface 31 ". As shown in the figure, each optical sensor PS is located on the optical axis of the corresponding convex lens L. In this example, a minute sensor surface of each optical sensor PS is a “minute light receiving region”.

  The light shielding means 20 has a parallel plate shape, and is disposed between the lens array 10 and the light receiving means 30, and each convex lens L and the corresponding “micro light receiving area (micro sensor surface of the optical sensor PS)”. Are formed corresponding to the arrangement of the convex lenses L of the lens array 10, and the visual field area for each convex lens L in the lens array 10 is made independent for each minute light receiving area. . In FIG. 1A, symbol H indicates a wall portion that separates holes forming a non-reflective light guide. The wall portion H which is the “peripheral wall of the hole” is light-shielding. In order to make the light shielding means 20 light-shielding, the light shielding means 20 may be formed of a light-shielding material, or may be formed of another material and a light-shielding paint may be applied to the hole or other part. .

  FIG. 1B shows an arrangement of four convex lenses L as a part of a square arrangement of convex lenses L in the lens array 10 and “holes forming a non-reflecting light guide path” corresponding to these four convex lenses. The relationship of the light shielding means 20 is shown. When viewed from the optical axis direction of the convex lens L, the wall portion of the light shielding means 20 is configured such that the peripheral surface of the hole is close to the lens periphery of the convex lens L as shown in the figure. This is a measure for preventing light from a visual field region corresponding to an adjacent convex lens from acting as stray light for one convex lens, “making the visual field region for each convex lens L independent for each minute light receiving region”. It is one of the measures for this. Instead of doing this, it is also possible to prevent the light from the visual field region corresponding to the adjacent convex lens from acting as stray light by increasing the length of the hole of the light shielding means 20.

  FIG. 1C shows the relationship between the arrangement of the four convex lenses L and the “field of view” corresponding to these four convex lenses as “a part of the square arrangement” of the convex lenses L in the lens array 10. Yes. The field of view indicated by reference sign S is set to be “close to each other” corresponding to the two-dimensional array of convex lenses L. Referring to an example of one convex lens L1 shown in FIG. 1C and the corresponding visual field region S1, the visual field region S1 is on the optical axis of the corresponding convex lens L1, and light from the visual field region L1 (near infrared) Light) is guided to the light receiving means only by the convex lens L1 corresponding to the visual field region S1. In order to realize this, the light shielding means 20 is used.

  As the light source means 41 and 42, an appropriate light source having a light emission wavelength in a wavelength region of about 700 to 1000 nm, for example, a semiconductor laser, a solid-state laser, an LED, or the like can be used, and the finger 0 is illuminated from the contact surface 11 side. To do. In this example, there are two light source means, but more illumination means may be provided. Further, one or more illumination means may be provided above the finger 0 in FIG. 1, and the finger 0 placed on the contact surface 11 may be illuminated from above.

  As shown in FIG. 1A, when a person to be authenticated who receives biometric authentication causes the light source means 41 and 42 to emit light with the finger 0 in contact with the contact surface 11, the emitted near-infrared light is emitted from the finger. 0 enters and is uniformly scattered by muscles, fat, bone tissue and the like inside the finger 10, but is absorbed by hemoglobin in the vein portion. As a result, the vein part 01 located 1 to 2 mm from the surface of the finger 0 that has contacted the contact surface 11 is positioned and can be read, and the inside of the finger (above in FIG. 1A) is higher than the vein part 01. ) Will become a “background having a substantially uniform density with respect to the vein portion 01” due to the scattering of near-infrared light.

  The vein portion 01 is the “state of the vein closest to the contact surface” to be detected, and is called the “test vein pattern” earlier, and will be referred to as the test vein pattern 01 hereinafter.

  FIG. 1D schematically illustrates a state in which near-infrared light from the surface including the subject vein pattern 01 is guided to the minute light receiving region by each convex lens of the lens array. Reference numerals L11 and L12 denote two convex lenses adjacent to each other in the lens array 10, and reference signs PS11 and PS12 denote optical sensors corresponding to the convex lenses L11 and L12 (the minute sensor surface is a minute light receiving area). .

  Reference numerals S11 and S12 are visual field regions corresponding to the convex lenses L11 and L12, respectively. Light from a portion located in the visual field region S11 of the test vein pattern 01 is guided to the corresponding optical sensor PS11 by the convex lens L11, and Light from the portion located in the visual field region S12 of the venous pattern 01 is guided to the corresponding optical sensor PS12 by the convex lens L12. At this time, since the “field region for each convex lens is independent for each minute light receiving region” by the action of the light shielding means 20, the light from the field region S 11 is not guided to the optical sensor PS 12. Light from the region S12 is not guided to the optical sensor PS11.

In this embodiment, as shown in FIG. 1D, the light from each field area forms a reduced image on the minute light receiving area by the corresponding convex lens.
In FIG. 1 (d), reference symbol P denotes an optical sensor arrangement pitch, which is the same as the arrangement pitch of convex lenses and the arrangement pitch of holes forming a non-reflective light guide.

  In this way, “an output signal corresponding to the amount of received light” is obtained from all the optical sensors PS of the light receiving means 30. The optical sensor array in the light receiving means 30 is expressed as PSij as a matrix, the visual field array corresponding to each of the optical sensors is expressed as Sij, and the output signal output from the optical sensor: PSij is expressed as SGij, i = 1 to n, j = 1 to m, “reading area (area inputted as image information)” of the vein pattern 01 to be examined corresponds to “matrix of visual field area: entire Sij”. Output signal: corresponding to SGij (i = 1 to n, j = 1 to m).

The total number of output signals obtained from the light receiving means 30 is “n × m”.
Accordingly, near-infrared light from the surface including the subject vein pattern 01 inside the human body surface that is in contact with the contact surface 11 is transmitted to the corresponding minute light-receiving region by the individual convex lenses of the lens array 10, and the minute light-receiving region The amount of received light is 1 pixel information SGij, and the image information of the vein part 01 to be authenticated is configured. That is, information for each field of view: Sij of the vein pattern to be examined is input as “image information represented by the total of output signal: SGij” as information for one pixel.

  In other words, the blood vessel image input apparatus described with reference to FIG. 1 is a vein authentication blood vessel image input apparatus, and is formed by arraying minute convex lenses L in an array density of 200 dpi to 500 dpi. A light receiving means 30 having a flat lens array 10, a minute light receiving region (a minute sensor surface of the optical sensor SP) corresponding to each convex lens L of the lens array 10 on the light receiving surface 31, and a lens array. 10 and the light receiving means 30, and a hole that forms a non-reflective light guide path between each convex lens and the corresponding minute light receiving region corresponds to the arrangement of the convex lenses L of the lens array 10. The light shielding means 20 that is formed and makes the field area for each convex lens L in the lens array 10 independent for each minute light receiving area, and the illumination hand that illuminates the vein portion 01 to be captured as an image with near infrared light The contact surface 11 is formed as a positioning portion for positioning the human body surface close to the vein portion 01 to be authenticated at a predetermined proximity position from the lens surface array in the lens array 10. Near-infrared light from the surface including the vein portion 01 inside the surface of the contacted human body is transmitted to the corresponding minute light-receiving region by the individual convex lenses of the lens array 10, and the amount of light received for each minute light-receiving region is one pixel information. Constitutes the image information of the vein part 01 to be authenticated (claim 1).

Further, each of the minute light receiving regions corresponding to 1: 1 for each convex lens L of the lens array 10 is configured by one light receiving unit (sensor surface of the optical sensor PS), and the output of one light receiving unit is one pixel information. (Claim 2).
Each convex lens L of the lens array forms an image that is not more than 1 times as large as the vein in the field of view on the minute light receiving area SP of the light receiving means 30 (Claim 5), and one surface of the lens array 10 is formed in a plane. A lens array of minute convex lenses L is formed on the other surface, the surface on which the lens array is formed is directed toward the light receiving means 30, and the surface formed on the flat surface is a vein portion to be authenticated. A positioning part 11 for positioning the surface of a nearby human body is formed (Claim 6), and the light shielding means 20 disposed between the lens array 10 and the light receiving means 30 is in the optical axis direction (vertical direction in FIG. One end of the lens is brought into contact with the lens array 10 and the other end is brought into contact with the light receiving surface 31 of the light receiving means 30 to function as a spacer that keeps the distance between the lens array 10 and the light receiving means 30 (Claim 7). Convex height in array 10 Sequence of small light receiving area is two-dimensionally in the array and the light receiving means 30's (claim 8).

  Further, the lens array 10, the light receiving means 30, and the light shielding means 20 are provided with a contact surface 11 for contacting a human body surface close to a vein portion to be authenticated at a predetermined proximity position from the lens surface array in the lens array 10. The “blood vessel image reading apparatus” according to Item 10 is configured.

  FIG. 3 shows two examples of modifications of the embodiment of FIG. In order to avoid confusion, the above description is used with the same reference numerals as those in FIG.

The difference between the embodiment shown in FIG. 3 and the embodiment shown in FIG. 1 is mainly in the form of light receiving means and light shielding means.
3 (a) and 3 (b), the light receiving means 32 is used. This light receiving means 32 is compared with the arrangement pitch P of the convex lenses L11, L12,. The small light receiving portions PS1 are uniformly arranged at a small pitch. As such light receiving means, a normal CCD area sensor, CMOS sensor or the like can be used.

  Thus, since the arrangement pitch of the minute light receiving portions PS1 is smaller than the arrangement pitch P of the convex lenses L11, L12,... In the lens array 10, the minute correspondence corresponding to each convex lens of the lens array 10 is 1: 1. Each of the light receiving areas is “configured by a plurality of light receiving portions PS1”.

  On the other hand, in the example shown in FIG. 3A, the “side in contact with the light receiving surface 31” of the light shielding means 21 has a plate shape, and “of each hole forming the non-reflective light guide path of this plate-like portion, The size of the “opening on the light receiving means side” is smaller than that on the lens array 10 side. Further, in the example shown in FIG. 3B, “each hole forming the non-reflecting light guide path” in the light shielding unit 22 has a peripheral surface of the hole from the lens array 10 side toward the light receiving unit 32 side. The taper is formed so that the hole diameter becomes small.

  In each of the examples shown in FIGS. 3 (a) and 3 (b), the opening on the light receiving means 32 side of each hole forming the non-reflecting light guide path of the light shielding means is “a light receiving portion constituting each minute light receiving area”. The “PS1 sequence region” is defined. The reason why the “opening portion on the light receiving means side” of each hole forming the non-reflecting light guide path of the light shielding means is smaller than the opening portion on the lens array side is that each convex lens L11, L12,. This is because a reduced image of each visual field region S11, S12,... Of the subject vein pattern 01 is formed on the light receiving surface. However, this is not a necessary condition, and “the hole diameter of the hole forming the non-reflecting light guide path may be uniform in the optical axis direction”.

  In the example shown in FIG. 3, the micro light receiving area is configured by “an array of a plurality of light receiving portions PS <b> 1”, but the amount of light guided to one micro light receiving area is only used as information for one pixel. In these examples, "the output sum of the plurality of light receiving portions PS1 constituting one minute light receiving region constitutes one pixel information".

  That is, the blood vessel image input device (the portion of the blood vessel image reading device is shown in the figure) showing the embodiment in FIG. 3 has a 1: 1 correspondence with each convex lens of the lens array 10 as its characteristic portion. Each of the small light receiving regions to be formed is composed of a plurality of light receiving portions PS1, and the output sum of the plurality of light receiving portions constitutes one pixel information (Claim 3). .. Arrangement pitch of convex lenses L11, L12... Small light receiving portions PS1 are uniformly arranged at a pitch smaller than P, and each of the holes forming the non-reflective light guide paths of the light shielding means 21 and 22 The opening on the light receiving means 32 side defines an array region of the light receiving portions PS1 constituting each minute light receiving region (Claim 4).

  In each of the embodiments described above, the “finger test vein pattern” is an object of image input. The size of the blood vessel image reading apparatus is about 2 mm at most and the area is about 15 mm × 10 mm. Is.

  In the embodiment shown in FIG. 4, the vein pattern to be examined is the “palm vein pattern” of the hand HN, and the blood vessel image reading having a large area of, for example, about 40 mm × 50 mm corresponding to the large detection area. The apparatus 100 is used. In this case, for example, illumination having one or a plurality of illumination light sources (not shown) may be provided on the “back side of the hand” so as to irradiate from the back side of the hand.

  In the case where “the detection area is large” as in this case, instead of using the “single blood vessel image reading apparatus 100 having a large area” as shown in FIG. 4, the example of FIG. The blood vessel image reading devices 101, 102,... 10i,... 10N having a relatively small area as described above may be provided to cover the detection area. In this case as well, for example, illumination having one or a plurality of illumination light sources (not shown) may be provided on the “back side of the hand” so as to irradiate from the back side of the hand. Further, the blood vessel image reading devices 101, 102,... 10i,... 10N may have different heights in the direction orthogonal to the drawing according to the irregularities of the palm.

  Further, when a plurality of blood vessel image reading devices having a relatively small area are used, as shown in FIG. 6, the blood vessel image reading devices 101, 102, 103, and 104 are used to “test vein patterns of different parts of two fingers”. ", Or as shown in FIG. 7, the blood vessel image readers 101, 102, and 103 can be used to input" test vein patterns of different parts of one finger ".

  In the example of FIG. 7, the blood vessel image readers 101, 102, and 103 are used to input the test vein pattern of “parts with different length directions” of one finger. For example, as shown in FIG. As in the example, the blood vessel image reading devices 111, 112, and 113 may be arranged so as to be inclined in accordance with the front and both sides of the finger 0 so as to read a wide range of test vein patterns 011, 012, and 013. . 6, 7, and 8, illumination may be performed from the back of the finger, or from the contact surface side as in the example described in FIG. 1.

  That is, in the embodiment shown in FIGS. 5, 6, 7 and 8, a plurality of blood vessel image reading devices are arranged and read according to a desired region on the human body surface having a vein portion to be authenticated. The region is illuminated with near infrared light by one or more illumination means.

  In the above description, the case where the arrangement of the convex lenses in the lens array and the arrangement of the micro light receiving areas in the light receiving means are two-dimensional has been described. However, as in the embodiment shown in FIG. Using the one-dimensional arrangement of the convex lenses in the array and the minute light-receiving areas in the light receiving means, the finger 0 is shifted in the direction of the arrow, and the test vein pattern in the two-dimensional area is read and input. it can. Illumination may be performed from one side of the finger using one or more light sources, or from the back side of the finger.

  Supplementally, the two-dimensional arrangement of the convex lenses in the lens array is not limited to the square arrangement described above, but may be a staggered arrangement. In addition, since the shape of the viewing area is determined by the arrangement form of the convex lenses, for example, if the arrangement of the convex lenses is a dense hexagonal shape (honeycomb shape), the shape of the viewing area also becomes a honeycomb shape. The peripheral shape of the lens surface of the convex lens is not limited to a circular shape, but a hexagonal shape, a triangular shape, or a quadrangular shape, and the “shape of the hole forming the non-reflecting light guide path” of the light shielding member is also the peripheral portion of the lens surface. It can be matched with the shape.

  In addition, a binning process can be performed on data output as input image information to reduce the data size and the processing time.

  Finally, a specific example regarding the portion of the blood vessel image reading apparatus in the embodiment shown in FIG. 1 will be given as an example.

A lens array 10 having a convex lens arrangement pitch of P = 0.1 mm was used, and the imaging magnification of each convex lens was set to 0.25 times. The arrangement of the convex lenses was a two-dimensional square arrangement, and the effective lens area of the convex lens was a circular area having a diameter of 0.08 mm. The field of view of the convex lens for the subject vein pattern 01 was a square with one side of 0.1 mm.
The holes forming the non-reflective light guide in the light shielding means 20 are two-dimensional with an arrangement pitch of 0.1 mm corresponding to the arrangement of the convex lenses, and the shape of the hole viewed from the optical axis direction is a circle having a diameter of 0.082 mm. Square array. The hole diameter of the hole forming the non-reflecting light guide is uniform in the optical axis direction.

  The small light receiving surface of the light receiving part PS in the light receiving means 30 is a “square shape with a side of 0.025 mm”, and a two-dimensional square array with an array pitch of 0.1 mm corresponding to the array of convex lenses. The distance from the light receiving surface 31 of the light receiving means 30 to the contact surface 11 is 0.76 mm, and the vein pattern 01 to be examined has a “object distance to the lens array 10” of 1 mm (position inside the finger 0). Further, in order to prevent visible light from acting as stray light, a filter film that transmits near infrared light and blocks visible light is formed on the contact surface 11.

  Based on the above conditions, the simulation shows how the light from the vein pattern to be examined is guided to each minute light receiving region when the vein thickness is 1 mm and 0.1 mm by simulation. Examined. The results are shown in FIGS. 2 (a) and 2 (b).

  2A shows a case where the blood vessel thickness is 1 mm, and FIG. 2B shows a case where the blood vessel thickness is 0.1 mm. The horizontal axis in these figures indicates “distance in the vein thickness direction” in mm, and the position corresponding to the central portion in the vein thickness direction is set to zero. Further, the vertical axis indicates the amount of light received by the light receiving unit PS, which is a minute light receiving area, and decreases upward, with the light amount on the vertical axis being 0.0 and the light amount on the bottom being 1.

  As can be seen from the figure, the veins with diameters of 1 mm and 0.1 mm can be read with extremely high resolution.

It is a figure for demonstrating one Embodiment of the blood-vessel image input device. It is a figure which shows the simulation result in an Example. It is a figure for demonstrating the characteristic part of another embodiment of the blood-vessel image input device. It is a figure for demonstrating the other form of implementation of the blood vessel image input device. It is a figure for demonstrating the other form of implementation of the blood vessel image input device. It is a figure for demonstrating the other form of implementation of the blood vessel image input device. It is a figure for demonstrating the other form of implementation of the blood vessel image input device. It is a figure for demonstrating the other form of implementation of the blood vessel image input device. It is a figure for demonstrating the other form of implementation of the blood vessel image input device.

Explanation of symbols

0 finger 01 Vein part to be authenticated (test vein pattern)
10 Lens array
20 Shading means
30 Light receiving means
L convex lens
PS Micro light receiving area (optical sensor)
S field of view

Claims (11)

A blood vessel image input device for vein authentication,
A parallel plate lens array in which minute convex lenses are arrayed at an array density of 200 dpi to 500 dpi;
A light receiving means having a minute light receiving area corresponding to 1: 1 on each convex lens of the lens array on the light receiving surface;
A hole disposed between the lens array and the light receiving means and forming a non-reflective light guide path between each convex lens and the corresponding minute light receiving region corresponds to the arrangement of the convex lenses of the lens array. A light-shielding means for independently forming a field area for each convex lens in the lens array for each minute light-receiving area,
Illuminating means for illuminating a vein portion to be captured as an image with near infrared light,
A positioning part for positioning the human body surface close to the vein part to be authenticated is formed at a predetermined proximity position from the lens surface array in the lens array,
Near-infrared light from the surface including the vein portion on the surface of the human body positioned by the positioning unit is transmitted to the corresponding minute light receiving region by the individual convex lenses of the lens array, and received by each minute light receiving region. A blood vessel image input device, characterized in that the image information of the vein portion to be authenticated is configured as one pixel information. The blood vessel image input device according to claim 1.
A blood vessel image input characterized in that each convex light-receiving area corresponding to 1: 1 is composed of a single light-receiving unit on each convex lens of the lens array, and the output of the single light-receiving unit constitutes one pixel information. apparatus. The blood vessel image input device according to claim 1.
Each of the minute light receiving areas corresponding to each convex lens of the lens array 1: 1 is composed of a plurality of light receiving parts, and the blood vessel image input is characterized in that the output sum of these light receiving parts constitutes one pixel information apparatus. The blood vessel image input device according to claim 3,
The light receiving means is a uniform array of minute light receiving portions at a pitch smaller than the arrangement pitch of convex lenses in the lens array,
A blood vessel image input device characterized in that the opening on the light receiving means side of each hole forming a non-reflective light guide path of the light shielding means defines an array region of the light receiving portions constituting each minute light receiving region. The blood vessel image input device according to any one of claims 1 to 4,
A blood vessel image input device, wherein each convex lens of a lens array forms an image of a vein portion or less in a visual field region on or near a minute light receiving region of a light receiving means. The blood vessel image input device according to any one of claims 1 to 5,
One surface of the lens array is formed in a plane, a lens array of minute convex lenses is formed on the other surface, and the surface on which the lens array is formed is directed toward the light receiving means, and is formed on the plane. A blood vessel image input device, wherein the surface forms a positioning unit for positioning a human body surface close to a vein portion to be authenticated. In the blood vessel image input device according to any one of claims 1 to 6,
A light blocking means disposed between the lens array and the light receiving means makes one end in the optical axis direction contact the lens array and the other end contact the light receiving surface of the light receiving means. It functions as a spacer which keeps the space | interval of the blood vessel image input device characterized by the above-mentioned. In the blood vessel image input device according to any one of claims 1 to 7,
A blood vessel image input device characterized in that the arrangement of convex lenses in the lens array and the arrangement of minute light receiving areas in the light receiving means are two-dimensional. In the blood vessel image input device according to any one of claims 1 to 7,
A blood vessel image input device characterized in that the arrangement of convex lenses in the lens array and the arrangement of minute light receiving areas in the light receiving means are one-dimensional.   A blood vessel image input device according to any one of claims 1 to 9, comprising a lens array, a light receiving means, and a light shielding means, and at a predetermined proximity position from the lens surface array in the lens array to a vein portion to be authenticated. A blood vessel image reading apparatus, wherein a positioning portion for positioning a near human body surface is formed.   A plurality of blood vessel image reading devices according to claim 10 are arranged in accordance with a desired region on the surface of a human body having a vein portion to be authenticated, and the region to be read is illuminated with near infrared light by one or more illumination means. A blood vessel image input device configured as described above.

Images