JP5030530B2 - Light emitting element array and paper sheet recognition device - Google Patents

Description

  The present invention generally relates to a light emitting element array and a paper sheet recognition apparatus. The present invention relates to an apparatus for recognizing paper sheets used in a discriminating apparatus that reads a print pattern such as a printed matter or a description item in a financial terminal device, a printing device, etc., and inspects the authenticity of the printed matter or print quality.

  The paper sheet recognition device is, for example, a device used for recognizing the shape of a paper sheet or the like in a banknote or securities discrimination device in a financial terminal device or a printing device. The paper sheet recognition apparatus includes a sensor in which light receiving elements are linearly arranged on a substrate, a bar-shaped illumination device for illuminating a document, and a light for transmitting or reflecting the document to each light receiving element. And a lens array.

As such a paper sheet recognition apparatus, Japanese Patent Application Laid-Open No. 2006-39996 discloses that the shape of a paper sheet can be accurately recognized, can be stably read, and the amount of emitted light and the optical axis can be determined. A paper sheet recognition device for the purpose of suppressing variations is disclosed (Patent Document 1).
JP 2006-39996 A

  FIG. 14 is a diagram illustrating an illuminating device that illuminates paper sheets in the prior art. In the figure, the path of light toward the paper is schematically shown. Referring to FIG. 14, lighting apparatus 101 includes a light source unit 120 and a light guide 107. The light source unit 120 is provided on each side of the light guide 107. A gap 111 is formed between the light source unit 120 and the light guide 107. The light guide 107 is formed with a light diffusion layer 109 for emitting light incident from the light source unit 120 toward the paper sheet 105.

  FIG. 15 is a perspective view showing the light source unit in FIG. FIG. 16 is a cross-sectional view of the light source unit along the line XVI-XVI in FIG. Referring to FIGS. 15 and 16, the light source unit 120 in the related art includes a plurality of LED (Light Emitting Diode) chips 125. The LED chip 125 is die-bonded on the lead frame 131 and mounted with a wire 127. The LED chip 125 is disposed in the chamber 137. The chamber 137 is molded with a white resin 135 and opened in one direction. The chamber 137 is filled with a transparent resin 133 that covers the LED chip 125. As the transparent resin 133, an epoxy resin, a silicone resin, or the like is used.

  Referring to FIGS. 14 to 16, the light emitted from LED chip 125 and transmitted through transparent resin 133 enters light guide 107. The light is reflected from the light diffusion layer 109, and is emitted from the light guide 107 to irradiate the paper sheet 105. The light transmitted through or reflected by the paper sheet 105 is received by a sensor (not shown), thereby reading the print pattern of the paper sheet 105 or the like.

  In the light source unit 120 having such a configuration, an acid anhydride curable epoxy resin is generally used as the transparent resin 133. However, in recent years, blue LEDs and green LEDs using short-wavelength GaN have been increased in luminance, and there is a risk that the epoxy resin around the chip will be discolored. In this case, there arises a problem that the amount of light emitted from the light source unit 120 decreases with the color change of the epoxy resin. On the other hand, as a countermeasure for preventing discoloration of the transparent resin 133, a cationic curable epoxy resin has been developed. However, when this resin is used, since the hardness of the resin is high, an LED chip using GaAs such as infrared rays deteriorates due to the stress of the resin. In these cases, the reliability of the light source unit cannot be maintained high.

  Further, in the illumination device 101 shown in FIG. 14, assuming the case where the light source unit 120 and the light guide 107 are arranged so as to be in contact with each other, the following points are problematic.

  FIG. 17 is a diagram for explaining deterioration of light distribution. Referring to FIGS. 16 and 17, when light source unit 120 and light guide 107 come into contact with each other, the light emitted from LED chip 125 is internally reflected at the boundary position between transparent resin 133 and light guide 107. Without being incident, it enters the light guide 107 directly. In this case, in the area close to the light source unit 120, in addition to the light reflected by the light diffusion layer 109 and traveling toward the paper sheet 105 (light traveling along the path indicated by the arrow 210 in the drawing), the paper sheet from the light source unit 120. Light directly traveling toward the sheet 105 (light traveling along the path indicated by the arrow 220 in the figure) irradiates the sheet 105. For this reason, the illuminance on the paper sheet 105 varies between an area close to the light source unit 120 and an area far from the light source unit 120, causing a problem that the orientation deteriorates.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a light emitting element array having high reliability and a paper sheet recognition apparatus using the light emitting element array. Another object of the present invention is to provide a paper sheet recognition apparatus that can accurately recognize the shape and the like of paper sheets and that can be stably read due to excellent light distribution.

The light emitting element array according to the present invention includes a first light emitting element and a second light emitting element, and one base material including the first chamber and the second chamber. The first light emitting element and the second light emitting element is electrically connected to each other emit light of different wavelengths, electrodes. The first chamber and the second chamber are opened in one direction and filled with resin. The first light emitting element and the second light emitting element are separately disposed in the first chamber and the second chamber, respectively, and are covered with resin.

  According to the light emitting element array configured as described above, the first light emitting element and the second light emitting element having different emission wavelengths are arranged separately in the first chamber and the second chamber, respectively. For this reason, resin suitable for covering the first light-emitting element and the second light-emitting element can be filled separately in the first chamber and the second chamber. Thereby, the reliability of the light emitting element array can be improved.

  Preferably, the first light emitting element emits light having a main emission wavelength of less than 570 nm. The second light emitting element emits light having a main emission wavelength of 570 nm or more and 980 nm or less. According to the light emitting element array configured as described above, it is possible to select an appropriate resin according to the type and wavelength range of each light emitting element.

  Preferably, the material or the hardness is different between the resin filling the first chamber and the resin filling the second chamber. According to the light emitting element array thus configured, various light emitting elements can be mounted, and the usability of the light emitting element array can be improved.

  A paper sheet recognition apparatus according to the present invention is a paper sheet recognition apparatus using the light-emitting element array described above. The paper sheet recognition device includes an illumination device that irradiates light on a paper sheet, a lens array that guides light emitted from the illumination device and transmitted or reflected by the paper sheet, and light guided by the lens array. A light receiving element for receiving light. The illuminating device has a light diffusing layer that emits incident light toward a paper sheet, a light guide that extends in a longitudinal direction, and light emission that is disposed near at least one end face of the light guide in the longitudinal direction. And an element array.

  According to the paper sheet recognition apparatus configured as described above, it is possible to read the shape, print pattern, and the like of the paper sheet using a plurality of emission wavelengths while maintaining high reliability.

  Preferably, the resin emits light emitted from the first light emitting element and the second light emitting element, and includes an emission surface having a concave shape. The light emitting element array is provided in contact with the end face of the light guide. According to the paper sheet recognition apparatus configured as described above, a gap can be provided between the emission surface and the end surface of the light guide by the configuration in which the emission surface has a concave shape. Thereby, the light distribution of the light irradiated toward paper sheets can be improved. Due to the excellent light distribution, it is possible to accurately recognize the shape of the paper sheet and perform stable reading.

  Preferably, the first light emitting element and the second light emitting element having different emission wavelengths are sequentially switched on. According to the paper sheet recognition apparatus configured as described above, it is possible to read a print pattern that is resolved for each light emission wavelength of each light emitting element.

  As described above, according to the present invention, it is possible to provide a light emitting element array having high reliability and a paper sheet recognition apparatus using the light emitting element array. In addition, it is possible to provide a paper sheet recognition apparatus that can accurately recognize the shape and the like of paper sheets and can be stably read due to excellent light distribution.

  Embodiments of the present invention will be described with reference to the drawings. In the drawings referred to below, the same or corresponding members are denoted by the same reference numerals.

  FIG. 1 is a cross-sectional view showing a paper sheet recognition apparatus according to an embodiment of the present invention. Referring to FIG. 1, a paper sheet recognition apparatus 10 according to the present embodiment is a transmission / reflection combination type recognition apparatus. The paper sheet recognition device 10 is disposed on one side with respect to the paper sheet (original) 15 and is disposed on the other side with respect to the protective glass 14m and the illuminating device 20m for transmission. The protective glass 14n, the reflection illumination device 20n, the lens array 13, the light receiving element 12, and the substrate 11 are provided.

  The illumination devices 20m and 20n emit light toward the paper sheet 15. The lens array 13 guides the light transmitted or reflected through the paper sheet 15 to the light receiving element 12. The light receiving element 12 receives light and reads an image as a light output by photoelectric conversion. The light receiving element 12 is mounted on the substrate 11. In the present embodiment, illumination device 20m, lens array 13 and light receiving element 12 are arranged on the same straight line. The illumination device 20n is arranged at a position shifted from the straight line.

  The material and structure of the light receiving element 12 are not particularly limited. Even if the photodiode or phototransistor including amorphous silicon, crystalline silicon, CdS, CdSe, or the like is disposed, or a CCD (Charge Coupled Device) linear image sensor. good. Further, as the light receiving element 12, a so-called multichip linear image sensor in which a plurality of ICs (Integrated Circuits) in which a photodiode, a phototransistor, a drive circuit, and an amplifier circuit are integrated may be used.

  Further, an electrical circuit such as a drive IC or an amplifier circuit or a connector for taking out a signal to the outside may be mounted on the substrate 11 as necessary.

  FIG. 2 is a block diagram for explaining the light receiving element in FIG. Further, as shown in the block diagram of FIG. 2, an A / D converter, various correction circuits, an image processing circuit, a line memory, an I / O control circuit, and the like are mounted on the substrate 11 at the same time so that digital signals are externally provided. It can also be taken out.

  The lens array 13 forms an image of the light scattered on the original surface of the paper sheet on the light receiving element 12 at an equal magnification. As the lens array 13, a rod lens array such as a SELFOC lens array (registered trademark: manufactured by Nippon Sheet Glass) can be used.

  The protective glasses 14m and 14n are not necessarily required for the present invention and can be omitted. However, in order to protect the illuminating devices 20m and 20n and the lens array 13 from scattering and scratching of dust in use, it is desirable to install protective glasses 14m and 14n. Further, the protective glasses 14m and 14n are not limited to glass, and may be members in which a hard coat is applied to the surface of a transparent resin such as acrylic or polycarbonate as necessary.

  FIG. 3 is an exploded view of the transmission illumination device in FIG. Referring to FIG. 3, lighting device 20 m includes a light guide 21 that extends in a longitudinal direction, a light source unit 30, and a cover 23 that holds light guide 21. A light diffusion layer 22 is formed on the light guide 21.

  The light guide 21 includes an end surface 21a and an end surface 21b. The end surface 21a and the end surface 21b are formed at both ends in the longitudinal direction in which the light guide 21 extends. Light source units 30 are provided in the vicinity of the end surface 21a and the end surface 21b, respectively. The two light source units 30 may be the same or different. For example, if LEDs having different emission wavelengths are installed in one light source unit 30 and the other light source unit 30, a plurality of wavelengths can be used simultaneously or by switching.

  The light source unit 30 is not limited to the configuration illustrated in FIG. 2, and may be disposed only at one end in the longitudinal direction in which the light guide 21 extends. The light source unit 30 is disposed in the vicinity of at least one end surface of the light guide 21 in the longitudinal direction.

  The light guide 21 includes an emission surface 21c. The emission surface 21c faces the paper sheet 15 in FIG. Light that passes through the light guide 21 and exits from the exit surface 21 c is irradiated toward the paper sheet 15. The emission surface 21c extends in the longitudinal direction in which the light guide 21 extends. The light diffusion layer 22 is formed to face the emission surface 21c.

  The light guide 21 is formed of a highly light-transmitting resin such as acrylic or polycarbonate, or optical glass. In particular, when an ultraviolet wavelength is used as the light source, it is preferable to use a fluorine resin or a cycloolefin resin as the light guide 21.

  FIG. 4 is an exploded view of the reflecting illumination device in FIG. FIG. 5 is a perspective view showing a light guide provided in the illumination device in FIG. 4. Referring to FIGS. 4 and 5, lighting device 20n and lighting device 20m in FIG. 3 have the same structure. The lighting device 20n includes a light guide 21 on which a light diffusion layer 22 is formed, a light source unit 30, and a cover 23. In the illumination device 20n, the light source unit 30 is disposed only on the end face 21a side. The light guide 21 has a trapezoidal cross-sectional shape when cut by a plane orthogonal to the longitudinal direction in which the light guide 21 extends.

  The light diffusion layer 22 has a pattern that is thinner toward the end surface 21a side where the light source unit 30 is disposed and has a smaller cut pitch, thicker toward the end surface 21b side where the light source unit 30 is not disposed, and larger in pitch. By forming the light diffusion layer 22 in such a pattern, the illuminance unevenness in the main scanning direction can be greatly reduced. The light diffusing layer 22 may be, for example, a white paint applied to the light guide 21 or unevenness formed on the surface of the light guide 21. The light diffusion layer 22 only needs to be capable of efficiently emitting light propagating through the light guide 21 from the emission surface 21c. The cross-sectional shape of the light guide 21 is not limited to the shape shown in FIG.

  The cover 23 reflects the light that has not reached the exit surface 21c out of the irregularly reflected light into the light guide 21 again, so that a molded product of a resin coated with a white resin or a white paint having a high light reflectance, Or it is preferable to form with metal plates, such as stainless steel and aluminum.

  FIG. 6 is a plan view showing the light source unit 30 provided in the illumination device in FIG. Referring to FIG. 6, light source unit 30 includes LED 41 and LEDs 42 and 43 having different emission wavelengths. The LED 41 emits light having a green wavelength. The LED 42 and the LED 43 emit light having red and near-infrared wavelengths, respectively. The LED 41 emits light having a main emission wavelength of less than 570 nm. The LED 42 and the LED 43 emit light having a main emission wavelength of 570 nm or more and 980 nm or less. The LED 41 emits light having a relatively small wavelength, and the LED 42 and the LED 43 emit light having a relatively large wavelength. The LED 41 is an LED using GaN. The LEDs 42 and 43 are LEDs using GaAs. The LED 41 may be an LED that emits light having a blue wavelength (470 nm). The LED 41 may be an LED that emits light having a wavelength of UV (365 nm, 375 nm).

  The LEDs 42 and 43 that emit light of red and near-infrared wavelengths are electrically connected to the lead frame 51p to which a positive voltage is applied by wire bonding. The LED 42 and the LED 43 are electrically connected to the lead frame 51q and the lead frame 51r to which a negative voltage is applied, respectively, by Ag paste. The LED 41 that emits light having a green wavelength is electrically connected to both the lead frame 51p to which a positive voltage is applied and the lead frame 51s to which a negative voltage is applied by wire bonding. That is, the LEDs 41 to 43 are electrically connected to the lead frame 51p that is the same common electrode.

  In addition, it is not limited to said connection form, Each LED needs to be electrically connected to a lead frame.

  FIG. 7 is a cross-sectional view of the light source unit along the line VII-VII in FIG. Referring to FIGS. 6 and 7, light source unit 30 includes a resin frame 31. Lead frames 51p, 51q, 51r and 51s (hereinafter referred to as lead frame 51 unless otherwise distinguished) are collectively supported by a resin frame 31.

  The resin frame 31 includes a chamber 32 and a chamber 33. The chamber 32 and the chamber 33 are formed by a recess that is molded into the resin frame 31 and opens in one direction. The resin frame 31 includes a top surface 31a facing the light guide 21 in FIG. The chambers 32 and 33 are formed by a recess opening in the top surface 31a. The chamber 32 and the chamber 33 are formed independently of each other. The lead frame 51p includes a main surface 51a to which the LEDs 41 to 43 are electrically connected. Chambers 32 and 33 are formed on main surface 51a. The wall surface of the resin frame 31 surrounding the chambers 32 and 33 is inclined so that the cross-sectional area of the chambers 32 and 33 obtained when cutting along a plane parallel to the main surface 51a gradually increases as the distance from the main surface 51a increases. .

  The LED 41 is disposed in the chamber 32. The LEDs 42 and 43 are disposed in the chamber 33. LED41 and LED42 and 43 are arrange | positioned separately.

  The resin frame 31 is formed of a resin that reflects light emitted from the LEDs 41 to 43. The resin frame 31 is preferably formed of a white resin in order to efficiently guide the light emitted from the LED to the front surface. The resin frame 31 is preferably formed of a heat resistant resin such as polybutylene terephthalate (PBT) or polyamide (PA) in order to withstand terminal soldering and heat generation of the LED.

  The chamber 32 and the chamber 33 are filled with a transparent resin 34 and a transparent resin 35, respectively. The LED 41 is covered with a transparent resin 34. The LEDs 42 and 43 are covered with a transparent resin 35. The transparent resins 34 and 35 are formed from a resin that transmits light emitted from the LEDs 41 to 43. The LEDs 41 to 43 are coated and protected by being sealed with transparent resins 34 and 35.

  The resin used for the transparent resins 34 and 35 is appropriately selected according to the type of LED disposed in the chambers 32 and 33. The transparent resin 34 and the transparent resin 35 differ in the material or hardness of the resin used. In the present embodiment, the LED 41 and the LEDs 42 and 43 having different emission wavelengths are separately mounted in the chamber 32 and the chamber 33, respectively. Therefore, these LEDs are sealed using a resin suitable for each LED. It becomes possible to do.

  For example, as the transparent resin 34 that seals the GaN-based high-power LED 41 that emits light having a green wavelength, a cation curable epoxy resin having excellent short wavelength resistance is used. As the transparent resin 34, it is also possible to use a modified silicone resin that has been developed in recent years. As the transparent resin 35 for sealing the GaAs LEDs 42 and 43 emitting red and near infrared light, a soft acid anhydride curable epoxy resin is used.

  With such a configuration, it is possible to prevent the transparent resin 34 from being discolored by light having a green wavelength emitted from the LED 41, and to prevent a decrease in the amount of light emitted from the light source unit 30. Further, it is possible to prevent the GaAs LEDs 42 and 43 from being deteriorated by the stress received from the transparent resin 35 and to maintain the reliability of the light source unit 30 high.

  The lead frame 51 is made of Ag alloy plated Cu alloy surface for reflecting light. When a silicone resin is used as the transparent resin, the gas permeability of the silicone resin is high, so that corrosion may occur at the Ag plating portion. On the other hand, when the above-mentioned cation curable epoxy resin, modified silicone resin or acid anhydride curable epoxy resin is used as the transparent resin, since these resins have low gas permeability, corrosion occurs. Can be prevented.

  Referring to FIG. 7, transparent resins 34 and 35 include an emission surface 36. Light emitted from the LEDs 41 to 43 and transmitted through the transparent resins 34 and 35 is emitted from the emission surface 36. The emission surface 36 has a concave shape. The emission surface 36 has a shape recessed from the top surface 31a. The emission surface 36 has a concave shape that is greatly recessed toward the center from the wall surface of the resin frame 31 forming the chambers 32 and 33. The emission surface 36 is configured by a curved surface. The top surface 31 a extends on the same plane at the boundary position between the chamber 32 and the chamber 33.

  Note that the emission surface 36 is not limited to the shape shown in FIG. 7, and may have, for example, a concave shape that is recessed from the top surface 31 a with a step, and may be configured by a flat surface.

  FIG. 8 is a diagram schematically showing a path of light emitted from the light source unit in FIG. Referring to FIG. 8, light source unit 30 is provided in contact with light guide 21. The top surface 31a of the resin frame 31 and the end surface 21a of the light guide 21 are in close contact with each other. Since the emission surface 36 has a concave shape, an air layer 37 is formed between the emission surface 36 and the light guide 21.

  By providing the air layer 37 between the emission surface 36 and the light guide 21, the light directly directed from the light source unit 30 to the paper sheet 15 can be more actively reflected by the end surface 21 a. Thereby, the light which is not reflected by the light diffusion layer 22 and directly irradiates the paper sheet 15 can be reduced, and the paper sheet 15 can be irradiated with light more uniformly. On the other hand, assuming that the light guide 21 is arranged with a gap between the light source unit 30 and the light guide 21 extending and contracting due to a temperature change, the light guide 21 is located between the light source 21 and the light source unit 30. There is a risk that the distance may change or the two may interfere. On the other hand, in the present embodiment, since the light source unit 30 and the light guide 21 are provided in contact with each other in advance, excellent light distribution can be stably obtained.

  The light source unit 30 as a light emitting element array in the embodiment of the present invention includes an LED 41 as a first light emitting element, LEDs 42 and 43 as second light emitting elements, a chamber 32 as a first chamber, and a chamber as a second chamber. And a resin frame 31 as a base material including 33. The LED 41 and the LEDs 42 and 43 emit light having different wavelengths and are electrically connected to a lead frame 51p as the same common electrode. The chamber 32 and the chamber 33 are opened in one direction and are filled with transparent resins 34 and 35 as resins. The LED 41 and the LEDs 42 and 43 are separately disposed in the chamber 32 and the chamber 33 and covered with transparent resins 34 and 35, respectively.

  The paper sheet recognition apparatus 10 includes illumination devices 20m and 20n that irradiate the paper sheet 15 with light, and a lens array that guides light that is emitted from the illumination devices 20m and 20n and transmitted or reflected by the paper sheet 15. 13 and a light receiving element 12 that receives light guided by the lens array 13. In the lighting devices 20m and 20n, a light diffusion layer 22 that emits incident light toward the paper sheet 15 is formed, and the light guide 21 that extends in the longitudinal direction and at least one of the longitudinal directions of the light guide 21 are formed. And a light source unit 30 as a light emitting element array disposed in the vicinity of the end face.

  According to the light source unit 30 and the paper sheet recognition apparatus 10 according to the embodiment of the present invention configured as described above, a plurality of wavelength light sources can be mounted on the light source unit 30 while maintaining high reliability. It becomes possible. Thereby, the print pattern of the paper sheet 15 can be easily read, and authenticity determination can be performed. Further, due to the excellent light distribution, the shape of the paper sheet 15 and the like can be accurately recognized, and stable reading can be performed.

  Next, various modifications and specific examples of the structures of the light source unit 30 and the paper sheet recognition apparatus 10 will be described.

  FIG. 9 is a plan view showing a first modification of the light source unit in FIG. Referring to FIG. 9, in the present modification, the light source unit 30 constitutes a five-color light source. The light source unit 30 includes an LED 61 and an LED 62 that emit light of green and blue wavelengths, respectively, and an LED 63, an LED 64, and an LED 65 that emit light of wavelengths of red, near infrared, and yellow, respectively. The LEDs 61 and 62 are disposed in a chamber 32 formed in the resin frame 31. The LED 63, LED 64 and LED 65 are arranged in a chamber 33 formed in the resin frame 31. The LEDs 61 to 65 are electrically connected to a lead frame 51p that is the same common electrode.

  FIG. 10 is a plan view showing a second modification of the light source unit in FIG. Referring to FIG. 10, in this modification, the light source unit 30 constitutes a three-color light source. The light source unit 30 includes two LEDs 71 that emit green light, and LEDs 72 and LEDs 73 that emit light of red and near-infrared wavelengths, respectively. The two LEDs 71 are arranged in a chamber 32 formed in the resin frame 31. The LED 72 and the LED 73 are arranged in a chamber 33 formed in the resin frame 31. The LEDs 71 to 73 are electrically connected to a lead frame 51p that is the same common electrode.

  In this modification, two LEDs 71 are mounted on different lead frames. This is because the light emission efficiency of the LED 71 that emits green light is poor, so that the light intensity is increased as a plurality in order to match the light output with other wavelengths. Note that the number of LEDs 71 mounted on each lead frame is not limited to one, and a plurality of LEDs 71 can be mounted simultaneously according to the purpose.

  The light source unit 30 is preferably caused to flash and emit light by a pulse signal having a predetermined cycle. In this way, when the light source is caused to blink by the pulse signal, the light emission intensity can be increased instantaneously, so that the S / N ratio (signal-to-noise ratio) can be increased. Thereby, stable reading is possible.

  In the present embodiment, the light source unit 30 includes a plurality of light emitting elements having different emission wavelengths. Thereby, if the light emission wavelength is switched in accordance with the scanning of the light receiving element 12, a print pattern separated in color for each wavelength can be read. Further, the emission wavelength can be arbitrarily selected depending on the target paper sheet. Specifically, if the scanning is performed by switching each color using the light emission wavelengths of three colors of red, green, and blue as described above, the printed pattern separated into RGB three primary colors can be read, and the three colors can be simultaneously read. If scanning is performed with light emission, a monochrome image by a white light source can be obtained. In addition, when near infrared is selected as the emission wavelength, the type of ink used in the printed material can be easily determined, and this is particularly suitable for applications such as authenticating bills.

An accumulation sensor can also be used for the light receiving element.
FIG. 11 shows an example of a timing chart in the case where a charge storage type linear image sensor having a configuration shown in Japanese Patent Publication No. 5-31865 is used as a light receiving element. Referring to FIG. 11, the LED 49a is first turned on to start accumulation, and immediately after the LED 49a is turned off, a start pulse is input to output a signal from the LED 49a. After the signal output of the LED 49a is completed, the respective signals of the LED 49b and LED 49c can be output to read one line.

  FIG. 12 shows an example of a timing chart in the case where charge accumulation and signal reading are performed independently. Referring to FIG. 12, first, LED 49a is turned on, a start pulse is input to perform accumulation, and at the same time, the previous accumulation signal (here, the signal of LED 49c) is output. After the LED 49a is turned off and the accumulation is completed, the LED 49b is turned on and a start pulse is input to perform accumulation, and at the same time, the LED 49a signal is output. In this way, it is possible to read one line by outputting a signal from the LED 49a to the LED 49c. The timing of FIG. 12 is particularly suitable for high-speed operation because the LED lighting time can be made longer than the timing of FIG.

  In addition, when switching a some LED as mentioned above, LED is inevitably pulse-driven (flashing light emission by a pulse signal).

  The paper sheet recognition device 10 according to the present embodiment shown in FIG. 1 includes two types of illumination devices for transmission and reflection, but only the reflection illumination device 20n functions as a recognition device and transmits. Only the lighting device 20m for use also functions.

  FIG. 13 is a sectional view showing a modification of the paper sheet recognition apparatus in FIG. Referring to FIG. 13, the paper sheet recognition apparatus in the present modification uses both a transmission type and a reflection type for both front and back surfaces. In addition to the configuration of the paper sheet recognition apparatus 10 according to the first embodiment, the paper sheet recognition apparatus includes an illumination device 81, a lens array 82, and a light receiving element disposed on one side with respect to the paper sheet 15. An element 83 and a substrate 84 are further provided.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is sectional drawing which shows the paper sheet recognition apparatus in embodiment of this invention. It is a block diagram for demonstrating the light receiving element in FIG. FIG. 2 is an exploded view of the transmissive illumination device in FIG. 1. FIG. 2 is an exploded view of the reflecting illumination device in FIG. 1. It is a perspective view which shows the light guide provided in the illuminating device in FIG. It is a top view which shows the light source unit 30 provided in the illuminating device in FIG. It is sectional drawing of the light source unit along the VII-VII line in FIG. It is a figure which represents typically the course of the light radiate | emitted from the light source unit in FIG. It is a top view which shows the 1st modification of the light source unit in FIG. It is a top view which shows the 2nd modification of the light source unit in FIG. FIG. 5 shows an example of a timing chart when a charge storage type linear image sensor having a configuration shown in Japanese Patent Publication No. 5-31865 is used as a light receiving element. FIG. 3 shows an example of a timing chart in the case where charge accumulation and signal reading are performed independently. It is sectional drawing which shows the modification of the paper sheet recognition apparatus in FIG. It is a figure which shows the illuminating device which illuminates the paper sheets in a prior art. It is a perspective view which shows the light source unit in FIG. It is sectional drawing of the light source unit along the XVI-XVI line | wire in FIG. It is a figure for demonstrating deterioration of light distribution.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Paper sheet recognition apparatus, 12 Light receiving element, 13 Lens array, 15 Paper sheets, 20m, 20n Illumination device, 21 Light guide, 21a, 21b End surface, 22 Light diffusion layer, 30 Light source unit, 31 Resin frame, 32, 33 chamber, 34, 35 transparent resin, 36 exit surface, 41-43, 61-65, 71-73 LED, 51p lead frame.

Claims (6)

Emit light of different wavelengths, a first light emitting element and the second light-emitting element electrically connected to the electrodes,
One substrate including a first chamber and a second chamber that are open in one direction and filled with resin;
The first light emitting element and the second light emitting element are separately disposed in the first chamber and the second chamber, respectively, and are covered with the resin. The light emitting element array according to claim 1, wherein a material or a hardness is different between the resin filling the first chamber and the resin filling the second chamber. The first light emitting element emits light of a main emission wavelength less than the wavelength 570nm, the second light emitting element emits light of a main emission wavelength 570nm or 980nm or less wavelength, according to claim 1 or claim 2 Light emitting element array. A paper sheet recognition device using the light emitting element array according to any one of claims 1 to 3,
A lighting device for irradiating the paper with light;
A lens array for guiding light emitted from the illumination device and transmitted or reflected by the paper sheet;
A light receiving element for receiving the light guided by the lens array,
The lighting device, disposed incident light extending longitudinally shaped light guide body where the light diffusing layer is formed to be emitted toward the paper sheet, the longitudinal direction of the at least one end near the surface of the light guide body And a light-emitting element array. The resin emits light emitted from the first light emitting element and the second light emitting element, and includes an exit surface having a concave shape,
The paper sheet recognition apparatus according to claim 4, wherein the light emitting element array is provided in contact with the end face. The paper sheet recognition apparatus according to claim 4 or 5, wherein the first light emitting element and the second light emitting element having different emission wavelengths are sequentially switched on.

Images