WO2021199422A1 - 照明装置及びイメージスキャナ - Google Patents

照明装置及びイメージスキャナ Download PDF

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Publication number
WO2021199422A1
WO2021199422A1 PCT/JP2020/015302 JP2020015302W WO2021199422A1 WO 2021199422 A1 WO2021199422 A1 WO 2021199422A1 JP 2020015302 W JP2020015302 W JP 2020015302W WO 2021199422 A1 WO2021199422 A1 WO 2021199422A1
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WO
WIPO (PCT)
Prior art keywords
light
incident
curved surface
light source
light guide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2020/015302
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English (en)
French (fr)
Japanese (ja)
Inventor
泰介 牧田
河野　裕之
秀 多久島
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP2022511479A priority Critical patent/JP7341319B2/ja
Priority to PCT/JP2020/015302 priority patent/WO2021199422A1/ja
Priority to DE112020007020.4T priority patent/DE112020007020T5/de
Priority to US17/912,857 priority patent/US12248165B2/en
Priority to CN202080099118.8A priority patent/CN115336241B/zh
Publication of WO2021199422A1 publication Critical patent/WO2021199422A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0033—Means for improving the coupling-out of light from the light guide
    • G02B6/005—Means for improving the coupling-out of light from the light guide provided by one optical element, or plurality thereof, placed on the light output side of the light guide
    • G02B6/0055—Reflecting element, sheet or layer
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/024—Details of scanning heads ; Means for illuminating the original
    • H04N1/028—Details of scanning heads ; Means for illuminating the original for picture information pick-up
    • H04N1/02815—Means for illuminating the original, not specific to a particular type of pick-up head
    • H04N1/0282—Using a single or a few point light sources, e.g. a laser diode
    • H04N1/02835—Using a single or a few point light sources, e.g. a laser diode in combination with a light guide, e.g. optical fibre, glass plate
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N1/00—Scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission; Details thereof
    • H04N1/04—Scanning arrangements, i.e. arrangements for the displacement of active reading or reproducing elements relative to the original or reproducing medium, or vice versa

Definitions

  • This disclosure relates to a lighting device and an image scanner.
  • a lighting device used in an image scanner mounted on a financial image reader or the like a region in which LED light is incident on a rod-shaped light guide body from an end face and the light is reflected in the long axis direction of the light guide body is formed.
  • a lighting device having the provided configuration is used.
  • An image is acquired by receiving the reflected light from the object illuminated by the lighting device with the light receiving element.
  • a method of injecting light into the light guide body a method in which the end surface of the light guide body is an incident surface and the light emitting surface of the LED is opposed to the end face of the light guide body in parallel is common.
  • the diameter of the light guide is reduced, the area of the end face is reduced, so that the incident efficiency of the light emitted from the light emitting surface of the LED is lowered.
  • a financial image reader that determines the authenticity of a bill, it is illuminated at multiple wavelengths using a plurality of LEDs that emit visible light (RGB light), infrared (IR) light, ultraviolet (UV) light, and the like.
  • RGB light visible light
  • IR infrared
  • UV ultraviolet
  • Patent Document 1 describes a technique for efficiently guiding light emitted from light emitting surfaces of a plurality of LEDs in the long axis direction.
  • the side surface of the light guide body is an incident surface
  • the light emitting surface of the LED is opposed to the side surface of the light guide body, and light is incident on the light guide body.
  • this method by making the end face of the light guide body a curved surface, the incident light is reflected by the curved surface and the light is guided in the long axis direction. Since the area of the side surface of the light guide body is larger than the area of the end surface, the proportion of the light emitted from the light emitting surface of the LED that is incident on the incident surface of the side surface of the light guide body is high.
  • an image is acquired using a plurality of single wavelength LEDs.
  • Ink that reflects only light of a specific wavelength is used for banknotes.
  • the five images obtained by separately illuminating the banknotes with, for example, five types of light, R, G, B, IR, and UV, have different characteristics such as patterns.
  • the authenticity of banknotes is determined based on a plurality of images acquired at each wavelength.
  • the LED closer to the end of the light guide has a higher light guide efficiency
  • the LED closer to the center of the light guide has a lower light guide efficiency.
  • the closer the LED is to the center of the light guide the smaller the inclination of the curved surface on which the light incident from the LED is reflected. Therefore, when the light reflected by the curved surface is next incident on the boundary between the light guide and the air, the incident angle becomes large and the proportion of light that does not satisfy the total reflection condition increases.
  • the narrower the LED spacing in the long axis direction the smaller the variation in the light guide efficiency between the LEDs, but the LED spacing cannot be narrowed due to the wiring around the LEDs and the heat dissipation of the LEDs.
  • the length of the curved surface in the long axis direction is also reduced, so that the influence of the LED spacing is relatively large.
  • the light guide efficiency varies between the LEDs arranged on the end side and the center side in the long axis direction of the light guide body, so that the illuminance level is adjusted. There is a problem that there are variations.
  • the present disclosure has been made to solve the above problems, and an object of the present disclosure is to reduce variations in light guide efficiency of light emitted from a plurality of light sources.
  • the lighting device includes a plurality of light sources and a light guide body that propagates while reflecting light incident on the inside, and the light guide body incidents light emitted from the plurality of light sources.
  • An incident portion having an incident surface and guiding the incident light toward the center in the long axis direction of the light guide body, and emitting the light guided from the incident portion toward the irradiated body.
  • a central portion having a scattering surface for the light is provided.
  • the plurality of light sources have a first light source having a light emitting surface facing the incident surface and a second light source having a light emitting surface facing the incident surface and arranged on the central portion side of the first light source. With a light source.
  • the incident portion includes a first curved surface that reflects light incident from the incident surface toward the central portion, and the incident portion is arranged on the central portion side of the first curved surface, and the light incident from the incident surface is referred to. It is characterized by having a second curved surface that reflects toward the central portion.
  • FIG. 1 It is an exploded perspective view which shows schematic structure of the image scanner which concerns on Embodiment 1.
  • FIG. It is an enlarged perspective view which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 1, and a plurality of light sources.
  • (A) is a diagram showing an example of an optical path of light emitted from a plurality of light sources, guided by a light guide body, and irradiated to an irradiated body in the lighting device according to the first embodiment
  • (B) is a diagram showing an example.
  • It is a graph which shows the illuminance distribution of an imaging range.
  • It is sectional drawing which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 1.
  • FIG. (A) to (C) are diagrams showing an optical path of light reflected by a paraboloid. It is sectional drawing which shows the incident part which has the curved surface of the parabolic surface shape of the light guide body of the lighting apparatus which concerns on Embodiment 1.
  • FIG. (A) and (B) are cross-sectional views showing an optical path of light in an incident portion of a light guide body of the lighting device according to the first embodiment.
  • (A) and (B) are cross-sectional views showing an optical path of light in an incident portion of a light guide body of the lighting device according to the first embodiment.
  • (A) and (B) are sectional views which show the range of the light guide emission angle in the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 1.
  • FIG. 1 A) and (B) are cross-sectional views showing an optical path of light in an incident portion of a light guide body of the lighting device according to the first embodiment.
  • FIG. 1 A) to (C) are cross-sectional views showing an optical path of light in an incident portion having a one-step curved surface of a light guide body of a lighting device of a comparative example.
  • (A) and (B) are cross-sectional views showing the range of the light guide emission angle in the incident portion having the one-step curved surface of the light guide body of the lighting device of the comparative example.
  • FIG.) to (C) are optical simulation diagrams showing an optical path in an incident portion having a two-stage curved surface of the light guide body of the lighting device according to the first embodiment.
  • FIG. (A) and (B) are optical simulation diagrams showing an optical path at an incident portion of a one-step curved surface of a light guide body of a lighting device of a comparative example. It is an enlarged perspective view which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 2, and a plurality of light sources. It is sectional drawing which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 2.
  • FIG. (A) to (C) are cross-sectional views showing the range of the light guide emission angle at the incident portion of the light guide body of the lighting device according to the second embodiment.
  • FIG. 1 It is an enlarged perspective view which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 3, and a plurality of light sources. It is sectional drawing which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 3.
  • FIG. 1 It is an enlarged perspective view which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 3, and a plurality of light sources. It is sectional drawing which shows the incident part of the light guide body of the lighting apparatus which concerns on Embodiment 3.
  • the lighting device and the image scanner according to the embodiment will be described below with reference to the drawings.
  • the following embodiments are merely examples, and it is possible to appropriately combine the embodiments and change the embodiments as appropriate.
  • the lighting device and the image scanner according to the embodiment are mounted on, for example, a financial image reader for reading banknotes and the like, but can also be mounted on devices such as copiers, facsimiles, and scanners.
  • the drawing shows the coordinate axes of the XYZ Cartesian coordinate system, which is a three-dimensional Cartesian coordinate system.
  • the X direction parallel to the X axis is a direction along the longitudinal direction of the light guide body (also referred to as a "major axis direction")
  • the Y direction parallel to the Y axis is a direction along the lateral direction of the light guide body. (Also called "minor axis direction").
  • the Z direction parallel to the Z axis is a direction from the sensor substrate toward the irradiated body (also referred to as a "height direction”).
  • the X'Z'coordinate system for example, FIGS. 6 and 7 described later
  • the X ′′ Z ′′ coordinate system for example, FIGS. 6 and 7 described later
  • X ′′ ′′ Z ′′ ′′ Coordinate systems
  • the irradiated body is an object to which light is irradiated by the lighting device according to the embodiment.
  • the irradiated body is an object to be read by the image scanner according to the embodiment.
  • FIG. 1 is an exploded perspective view schematically showing the configuration of the image scanner 100 according to the first embodiment.
  • the image scanner 100 guides light by a light source unit 1 having a plurality of light sources, an LED substrate 2 provided with an LED (Light Emitting Diode) as a light source, a lead wire 22, and light.
  • a rod-shaped light source 3, a scattering surface 4 for scattering light, a holder 5, a transmitter 6, an imaging optical system 7, a light receiving element 8 as an image sensor, and a light receiving element 8 are mounted. It has a light source 9 and a light source 9.
  • the light source unit 1 has, for example, a plurality of LEDs that emit visible light that is white light or red-green-blue (RGB) color light, a plurality of LEDs that emit invisible light that is IR light or UV light, and the like. ..
  • the light source unit 1 includes, for example, a package LED in which an LED chip is resin-molded, a bare chip LED composed of a bare chip, or an organic EL (Electroluminescence).
  • One or more light source units 1 are installed on the LED substrate 2.
  • two LED boards 2 are shown, and each LED board 2 is equipped with two light source units 1.
  • Each light source unit 1 has a plurality of light sources.
  • the plurality of light sources are, for example, a first light source 1a and a second light source 1b shown in FIG. 2 described later.
  • the number and arrangement of the light source units 1 are not limited to those in the example of FIG. Further, the number of light sources provided in each light source unit 1 may be three or more.
  • the lead wire 22 is a flexible cable or the like that supplies electric power to the light source unit 1.
  • the light guide body 3 is made of a transparent material.
  • the transparent material is, for example, a transparent resin such as acrylic or polycarbonate, glass, or the like.
  • the light guide body 3 has two incident portions 3a and a central portion 3b arranged between the incident portions 3a.
  • the number of incident portions 3a may be one.
  • two light guide bodies 3 are arranged side by side in the Y direction.
  • the number and arrangement of the light guide bodies 3 are not limited to those in the example of FIG.
  • the incident portion 3a has a function of guiding light incident from a plurality of light sources of the light source unit 1 toward the central portion 3b.
  • the central portion 3b is provided with a curvature in a part or the whole of a cross section cut by a plane parallel to the YZ plane. Providing a curvature in the cross section means that at least a part of the outer circumference of the cross-sectional shape is a curved line.
  • the cross-sectional shape of the central portion 3b is circular, elliptical, or the like.
  • a scattering surface 4 is provided on the surface of the central portion 3b.
  • the scattering surface 4 has a scattering pattern that changes periodically along the X direction, which is the long axis direction.
  • the scattering pattern of the scattering surface 4 has a function of scattering the light to be guided while totally reflecting the inside of the central portion 3b and emitting the light to the outside from the side surface of the light guide body 3.
  • the scattering surface 4 irradiates the irradiated body 10 in the + Z direction of the light guide body 3 with light.
  • the transparent body 6 is a cover glass of the image scanner 100.
  • the transmissive body 6 is composed of, for example, a plate-shaped transparent member.
  • the transmissive body 6 allows the passage of light and supports the irradiated body 10 such as a document or a banknote.
  • the imaging optical system 7 is a reading optical system that focuses the reflected light from the irradiated body 10 to form an optical image of the irradiated body 10.
  • the imaging optical system 7 is, for example, a rod lens array having a plurality of rod lenses.
  • the light receiving element unit 8 has a plurality of light receiving elements mounted in a line in the X direction on the sensor substrate 9, and constitutes a line sensor.
  • the light receiving element unit 8 has a function of converting an image formed by the imaging optical system 7 into an electric signal.
  • the holder 5 houses and holds the light guide body 3, the transmissive body 6, the imaging optical system 7, and the like, and fixes them on the sensor substrate 9.
  • the light receiving element unit 8 composed of a plurality of light receiving elements arranged in the X direction acquires one line of images with one exposure.
  • a single image (that is, image data) is acquired by transporting the irradiated body 10 in the Y direction, acquiring a plurality of line images, and arranging the acquired plurality of line images.
  • the line image of each color of RGB is formed by turning on the LED that emits the light of each color of RGB according to the exposure time of each color. To be acquired.
  • FIG. 2 is an enlarged perspective view showing an incident portion 3a and a light source portion 1 of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • the cross section of the incident portion 3a cut by a plane parallel to the YZ plane is a quadrangle.
  • One surface (lower surface in FIG. 2) of the side surface of the incident portion 3a is an incident surface 11 facing the first light source 1a and the second light source 1b of the light source unit 1.
  • the surface (upper surface in FIG. 2) of the incident portion 3a of the light guide body 3 facing the incident surface 11 is a curved surface portion 12 having a plurality of steps of curved surfaces having points at which the inclination changes discontinuously.
  • the curved surface portion 12 has a first curved surface 12a and a second curved surface 12b.
  • the cross section of the incident portion 3a that cuts the curved surface portion 12 in a plane parallel to the XZ plane has a shape that is curved so as to be convex toward the outside of the light guide body 3.
  • the first curved surface 12a is a surface that is convex in the normal direction of the light emitting surface of the first light source 1a and toward the outside
  • the second curved surface 12b is the light emitting surface of the second light source 1b. It is a surface that is convex in the normal direction and toward the outside.
  • the shape of the cross section obtained by cutting the incident portion 3a in a plane parallel to the YZ plane is a quadrangle.
  • this shape may be a shape having a curvature such as a circle or an ellipse, a polygon, a shape in which a curved line and a straight line are combined, and the like.
  • a surface other than the side surface facing the incident surface 11 may be curved in the X direction. In order to improve the light guide efficiency, it is desirable that the curved surface portion 12 which is a side surface facing the incident surface 11 is curved in the X direction.
  • FIG. 2 shows the positional relationship between the incident portion 3a of the light guide body 3, the light source portion 1, and the LED substrate 2.
  • the light source unit 1 has a plurality of LEDs that are a plurality of light sources (that is, a first light source 1a and a second light source 1b).
  • the plurality of LEDs are arranged in the X direction so as to have a light emitting surface facing the incident surface 11.
  • the plurality of LEDs may be arranged in the minor axis direction. At this time, it is desirable to narrow the distance between the light emitting surface of the LED and the incident surface 11 in the height direction (Z direction) as much as possible to improve the incident efficiency of light into the light guide body 3.
  • the LED substrate 2 By fixing the LED substrate 2 on the sensor substrate 9 and adjusting the thickness of the LED substrate 2, the light emitting surface of the LED and the incident surface 11 can be brought closest to each other.
  • a jig for adjusting the position of the LED substrate 2 in the Z direction may be separately prepared.
  • the LED substrate 2 and the sensor substrate 9 are separate substrates, but the LED may be mounted on the sensor substrate 9 by adjusting the position of the light guide body 3 in the Z direction. ..
  • the LED is a bare chip.
  • the size of the bare chip LED is, for example, 0.3 mm in width, 0.3 mm in length, and 0.2 mm in height.
  • the distance between the LEDs needs to be 0.6 mm or more due to heat dissipation and wiring.
  • the energizing wire protrudes 0.2 mm in the height direction from the surface of the LED, the distance between the LED and the incident surface 11 needs to be 0.2 mm or more.
  • the light source unit 1 may be a resin-molded LED or an LED with a lens. However, since it is difficult to narrow the distance between the plurality of LEDs, it hinders the miniaturization of the light guide body 3. Further, when a resin-molded LED is used, the distance between the light emitting surface of the LED and the incident surface 11 becomes wide, so that the light that does not enter the light guide body 3 increases.
  • FIG. 3A is a diagram showing an example of an optical path of light emitted from the light source unit 1 and guided by the light guide body 3 and irradiated to the irradiated body 10 in the lighting device 200 according to the first embodiment.
  • FIG. 3B is a graph showing the illuminance distribution in the imaging range.
  • FIG. 3A shows the path of the light emitted from the first light source 1a and the second light source 1b of the light source unit 1. The light emitted from the first light source 1a and the second light source 1b is incident on the light guide body 3, reflected by the curved surface portion 12, and propagates substantially in the X direction.
  • a part of the propagating light is incident on the scattering surface 4 and scattered, and is emitted to the outside of the light guide body 3 to irradiate the irradiated body 10.
  • it is desirable that the illuminance distribution in the imaging range is uniform.
  • the central portion 3b of the light guide body 3 By densely forming the scattering pattern of the scattering surface 4 provided near the center of the light source 3 and sparsely forming the scattering pattern of the scattering surface 4 on the end side of the central portion 3b of the light guide body 3, the illuminance in the imaging range. It is possible to make the distribution uniform.
  • the scattering of the scattering surface 4 on the side close to the first light source 1a and the second light source 1b is scattered.
  • FIG. 4 is a cross-sectional view showing an incident portion 3a of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • FIG. 4 shows a cross section of the incident portion 3a cut by a plane parallel to the XZ plane.
  • the two light sources are a first light source 1a arranged on the end side of the light guide body 3 in the X direction and a second light source 1b arranged on the center side of the light guide body 3 in the X direction. ..
  • the critical angle ⁇ 0 of the light is expressed by the following equation (1).
  • the incident angle ⁇ of the light incident on the interface with the air from the inside of the light guide 3 is smaller than the critical angle ⁇ 0 , the light passes through the interface, and if the incident angle ⁇ is the critical angle ⁇ 0 or more, the light is transmitted. Total internal reflection.
  • the refractive index n is 1.49 and the critical angle ⁇ 0 is 42.2 °.
  • the incident angles when the light incident on the inside of the light guide body 3 from the first light source 1a and the second light source 1b is reflected by the curved surface portion 12 and then incident on the side surface of the light guide body 3 are ⁇ a , respectively.
  • ⁇ b the light having ⁇ a > ⁇ 0 and the light having ⁇ b > ⁇ 0 guide the inside of the light guide body 3.
  • the shape of the cross section obtained by cutting the curved surface portion 12 with a plane parallel to the XZ plane may be a shape such as a circle or an ellipse.
  • the shape of the cross section obtained by cutting the first curved surface 12a and the second curved surface 12b of the curved surface portion 12 with a plane parallel to the XZ plane is a parabola. That is, each of the first curved surface 12a and the second curved surface 12b is a part of a parabolic surface which is a rotating body of a parabola. Further, when each of the first curved surface 12a and the second curved surface 12b is a part of the paraboloid, the height of the curved surface portion 12 in the Z direction can be lowered.
  • 5 (A) to 5 (C) are diagrams showing an optical path of light reflected by a paraboloid. Assuming that the origin is O in the xy coordinate system, the parabola y having the origin O as the apex is expressed by the following equation (2) using the radius of curvature R at the apex.
  • the light emitted from the light source 51 placed at the focal point F of the parabola y is reflected by the parabola and is parallel to the parabola axis (that is, the y-axis) (that is, that is). , + Y direction).
  • the light emitted from the light source 51 placed on the + y side of the focal point F travels closer to the parabolic axis (that is, the y-axis) when reflected by the parabola y.
  • the light emitted from the light source 51 placed on the ⁇ y side of the focal point F travels away from the parabolic axis (that is, the y-axis) when reflected by the parabola y. ..
  • the parabolic curved surface can be easily designed because the angle of the reflected light can be limited by the positional relationship between the light source 51 and the focal point F.
  • a part of the light emitted from the light source unit 1 and incident on the curved surface portion 12 may leak to the outside of the light guide body 3 without being reflected. Therefore, the light guide efficiency may be improved and the light utilization efficiency may be improved by forming a reflective film on the curved surface portion 12 by vapor deposition of aluminum or the like.
  • FIG. 6 is a cross-sectional view showing an incident portion 3a having a parabolic curved surface of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • FIG. 6 shows a cross section of the incident portion 3a cut by a plane parallel to the XZ plane.
  • the curved surface portion 12 is composed of a first curved surface 12a and a second curved surface 12b.
  • the first curved surface 12a and the second curved surface 12b are parabolas in a cross section cut by a plane parallel to the XZ plane.
  • the first curved surface 12a and the second curved surface 12b are connected by a discontinuity point 13. Although the discontinuity point 13 is a point in the cross section, it is actually a boundary line between the first curved surface 12a and the second curved surface 12b.
  • the parabolic line in the cross section of the first curved surface 12a has the end point 14 at the end of the light guide body 3 as the origin, and the XZ plane has an axis oriented in the + X direction and an axis oriented in the ⁇ Z direction, which is the height direction.
  • the X'axis and the Z'axis obtained by rotating the angle ⁇ a on a plane parallel to the X'axis, that is, the X'Z' coordinate system is used as a reference.
  • the equation of the parabola Z'by the first curved surface 12a is expressed by the following equation (3).
  • the parabola in the cross section of the second curved surface 12b has the discontinuity point 13 as the origin, and the angle between the axis facing the + X direction and the axis facing the ⁇ Z direction, which is the height direction, on a plane parallel to the XZ plane.
  • the X ′′ axis and the Z ′′ axis rotated by ⁇ b are used as a reference.
  • the radius of curvature at the origin is R b
  • the focal length L b is 2 R b
  • the equation of the parabola Z ′′ by the second curved surface 12 b is expressed by the following equation (4).
  • the length of the light guide body 3 in the Z direction is represented by H in FIG.
  • H 2 mm.
  • L 2 mm.
  • 7 (A) and 7 (B) are cross-sectional views showing an optical path of light in an incident portion 3a of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • the focal length 15a of the first curved surface 12a is determined to be a point having a focal length La in the Z'direction from the end point 14. As shown in FIG. 7A, the first light source 1a is placed at the focal point 15a. For ease of understanding of the description, the first light source 1a is drawn as a point. Actually, it is necessary to place the first light source 1a at a virtual focal position in consideration of the refraction of light on the incident surface 11. However, in this embodiment, it is assumed that there is no refraction on the incident surface 11.
  • the second light source 1b is a point for easy understanding of the explanation.
  • the light beam 16bA in FIG. 7B is a light beam emitted from the second light source 1b and reflected by the first curved surface 12a.
  • ⁇ b ⁇ 0
  • the light is guided in the + X direction.
  • 8 (A) and 8 (B) are cross-sectional views showing an optical path of light in the incident portion 3a of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • 9 (A) and 9 (B) are cross-sectional views showing a range of light guide emission angles at the incident portion 3a of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • FIG. 8A shows light rays other than the light rays 16aA (shown in FIG. 7A) emitted from the first light source 1a placed at the focal point 15a of the first curved surface 12a.
  • the light beam 16aB is a light ray that does not enter the incident surface 11, and increases as the first light source 1a approaches the end side of the light guide body 3 (here, in the ⁇ X direction).
  • the light ray 16aC is a light ray that is incident on the light guide body 3 and is reflected by the second curved surface 12b. Since the light beam 16aC is incident on the second curved surface 12b at a large incident angle, it is guided in the + X direction.
  • the light beam 16aD is a light ray that is directly incident on the flat surface portion on the + X direction side of the end point 17 of the second curved surface 12b, and leaks to the outside of the light guide body 3 without total internal reflection. Since rays 16aA and light 16aB light guide satisfies among the light emitted from the first light source 1a, is released into the range of the angle [psi a shown in FIG. 9 (A) (i.e., the range hatched) The light is guided inside the light guide body 3.
  • FIG. 8B shows light rays other than the light rays 16bA (shown in FIG. 7A) emitted from the second light source 1b placed at the focal point 15b of the second curved surface 12b.
  • the light beam 16bB is a light ray that does not enter the incident surface 11, and increases as the first light source 1a approaches the end side of the light guide body 3 (here, in the ⁇ X direction).
  • the light ray 16bC is a light ray reflected by the first curved surface 12a. Since the light beam 16bC is incident on the second curved surface 12b at a small incident angle, it leaks to the outside of the light guide body 3.
  • the light beam 16bD is a light ray that is directly incident on the flat surface portion on the + X direction side of the end point 17 of the second curved surface 12b, and leaks to the outside of the light guide body 3 without total internal reflection. Since been only light 16bA light guide satisfies among the light emitted from the second light source 1b, the range of the angle [psi b shown in FIG. 9 (B) (i.e., the range hatched) light emitted in Is guided inside the light guide body 3.
  • the first light source 1a is placed at the focal point 15a of the first curved surface 12a and the case where the second light source 1b is placed at the focal point 15b of the second curved surface 12b have been described.
  • the refraction generated at the incident surface 11 and that the first light source 1a and the second light source 1b are not points but surfaces having a width in the X direction, they are around the focal position, that is, the focal point.
  • the light source may be arranged at a position slightly deviated from the position.
  • FIG. 10A and 10 (B) are cross-sectional views showing an optical path of light in an incident portion 3a of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • the first light source 1a is arranged closer to the end of the light guide body 3 than the focal point 15a. Since the light ray 16aE emitted from the first light source 1a and reflected by the first curved surface 12a intersects the Z'axis between the end point 14 and the focal point 15a, the light ray 16aE is from the intersection 18a on the Z'axis. Proceeds in the same way as the emitted light. Therefore, as described in FIG.
  • the light reflected by the first curved surface 12a travels outward from the direction parallel to the Z'axis, and ⁇ a > ⁇ 0 .
  • the first light source 1a and the second light source 1b are arranged closer to the end of the light guide body 3 than the focal point 15a and the focal point 15b, respectively, the light guide body similar to the angle ⁇ a and the angle ⁇ b. It is possible to obtain an emission angle range that makes it possible to guide the inside of 3.
  • the first light source 1a and the second light source 1b are brought closer to the end side of the light guide body 3, they do not enter the incident surface 11 such as the light rays 16aB and the light rays 16bB in FIGS. 8A and 8B. Since the light increases and the angle ⁇ a and the angle ⁇ b become smaller, the light source efficiency decreases. Therefore, it is desirable that the first light source 1a is arranged closer to the center of the light guide 3 than the end point 14, and the second light source 1b is arranged closer to the center of the light guide 3 than the discontinuity 13.
  • refraction occurs at the incident surface 11, or because the first light source 1a and the second light source 1b have a certain width in the X direction.
  • ⁇ a > ⁇ 0 , ⁇ b > ⁇ 0 Therefore, it is desirable that the reflected light of the curved surface portion 12 has a margin with respect to the light guide condition.
  • the angles ⁇ a and ⁇ b of the inclination of the parabolic axis may be set to ⁇ a ⁇ 0 and ⁇ b ⁇ 0.
  • the first light source 1a and the second light source 1b are arranged at the focal points 15a and 15b, light that does not guide the light appears even if it is reflected by the curved surface portion 12, so that the light guide efficiency is improved. It is desirable to bring the light source 1a of 1 and the second light source 1b closer to the end side of the light guide body 3.
  • the lighting device 200 of the first embodiment with a comparative example in which the curved surface portion 12 does not have the discontinuity point 13 and is composed of one curved surface, the light is emitted from two light sources arranged in the X direction. It will be described that the variation in the light guide efficiency of the light is reduced by the first embodiment.
  • 11 (A) to 11 (C) are cross-sectional views showing an optical path of light in an incident portion 31a having a one-step curved surface of a light guide body of a lighting device of a comparative example.
  • 12A and 12B are cross-sectional views showing a range of light guide emission angles in the incident portion 31a having a one-step curved surface 12d of the light guide body of the lighting device of the comparative example.
  • the one-step curved surface 12d is one curved surface having no discontinuity.
  • FIG. 11A shows a cross section of a light guide body having one curved surface 12d cut by a plane parallel to the XZ plane.
  • the curved surface 12d is an end point 14 at the end of the first curved surface 12a as well as the light guide as the origin, the angle theta 0 rotating the parabola axis on the plane parallel to the XZ plane.
  • the length L'of the curved surface 12d in the X direction is equal to the length L of the first curved surface 12a and the second curved surface 12b of the first embodiment in the X direction.
  • the relationship between the radius of curvature R d of the curved surface 12d and the radius of curvature R a of the first curved surface 12a is R d > R a . Therefore, the focal length L d of the curved surface 12d becomes L d> L a.
  • the focal point of the curved surface 12d is 15d.
  • the light ray 17a in FIG. 11B is a light ray emitted from the first light source 1a and reflected by the curved surface 12d. Since the first light source 1a is on the end point 14 side of the focal point of the curved surface 12d, as shown in FIG. 5C, the light ray 17a is outside the line parallel to the Z'axis when reflected by the curved surface 12d.
  • FIG. 11C shows the light guiding state of the light beam emitted from the second light source 1b.
  • Whether or not the light emitted from the second light source 1b guides the inside of the light guide body depends on the position of the intersection with the Z'axis when the light ray is extended toward the Z'axis side.
  • the ray 17bA intersects the Z'axis at an intersection 18. Since the intersection 18 is on the + Z'side of the focal point 15c, as described in FIG. 5 (B), when reflected by the first curved surface 12a, it advances inward from parallel to the Z'axis. Therefore, ⁇ b ′ of the light ray 17 bA becomes ⁇ b ′ ⁇ 0 , and the inside of the light guide body is not guided.
  • the ray 17bB intersects the Z'axis at the intersection 19. Since the intersection 19 is on the end point 14 side of the focal point 15c, as described in FIG. 5 (C), when reflected by the first curved surface 12a, it advances to the outside of the Z'axis parallel. Therefore, ⁇ b ′′ of the light ray 17 bA becomes ⁇ b ′′> ⁇ 0 , and the inside of the light guide body is guided. Therefore, in the case of the second light source 1b, when light is emitted within the range of the angle ⁇ b ′ in FIG. 12 (B), this light is guided inside the light guide body.
  • ⁇ a ⁇ a ′, ⁇ b > ⁇ b ′
  • the magnitude relationship of the emission angle range for guiding light matches the magnitude relationship of the luminous efficiency.
  • 13 (A) to 13 (C) are optical simulation diagrams showing an optical path in an incident portion 3a having a two-stage curved surface of the light guide body 3 of the lighting device 200 according to the first embodiment.
  • 13 (A) to 13 (C) show a state in which the light emitted from the first light source 1a and the second light source 1b is guided in the X direction in the first embodiment.
  • the size of the light source is 0.3 mm ⁇ 0.3 mm, and the distance t between the incident surface 11 and the light emitting surface is 0.3 mm.
  • the light guide body 3 has a thickness H of 2 mm and a width W of 2 mm.
  • the first curved surface 12a and the second curved surface 12b have angles ⁇ a and ⁇ b of inclination of the parabolic axis of 45 °, which are larger than the critical angle ⁇ 0.
  • the total length of the curved surface portion 12 in the X direction is, for example, 4.2 mm.
  • the first light source 1a and the second light source 1b are arranged near the parabolic axes of the first curved surface 12a and the second curved surface 12b, respectively, and the distance between the first curved surface 12a and the second curved surface 12b in the X direction. Is 0.7 mm.
  • the curved surface portion 12 is subjected to aluminum vapor deposition processing. At this time, the light guiding efficiency of the light emitted from the first light source 1a shown in FIG. 13 (A) is 78%, and the light emitted from the second light source 1b shown in FIG. 13 (B). The light source efficiency of is 77%. As described above, there is little variation in the light guide efficiency of the light emitted from the first light source 1a and the light guide efficiency of the light emitted from the second light source 1b.
  • 14 (A) and 14 (B) are optical simulation diagrams showing the optical path at the incident portion 31a of the curved surface 12d of the first stage of the light guide body of the lighting device of the comparative example.
  • 14 (A) and 14 (B) show the state of the light guide when the curved surface 12d does not have the discontinuity point 13 and is composed of one curved surface.
  • the parameters other than the curved surface 12d are the same as those in the first embodiment.
  • the inclination of the parabolic axis of the curved surface 12d is also 45 °, which is the same as that of the first embodiment, and the length L of the curved surface 12d in the X direction is the total length of the first curved surface 12a and the second curved surface 12b of the first embodiment.
  • the light guiding efficiency of the light emitted from the first light source 1a shown in FIG. 14 (A) is 78%
  • the guidance of the light emitted from the second light source 1b shown in FIG. 14 (B) is The light efficiency is 61%.
  • the variation in the light guide efficiency of the light emitted from the first light source 1a and the light guide efficiency of the light emitted from the second light source 1b is larger than that in the case of the first embodiment. Moreover, the light source efficiency is reduced.
  • the first light source 1a and the second light source 1b arranged in the X direction facing the side surface of the light guide body 3 have a second light source.
  • the first light source 1a and the second light source 1b arranged in the X direction facing the side surface of the light guide body 3 have a second light source.
  • the two light sources (that is, the first light source 1a and the second light source 1b) are arranged side by side in the X direction, which is the long axis direction, and the two-stage curved surface portion 12 (that is, the first light source 1b) is arranged.
  • the curved surface 12a and the second curved surface 12b) are formed so as to be aligned in the X direction, and the light emitted from a plurality of light sources arranged in the X direction and incident on the inside of the light guide body 3 is guided in the X direction. ..
  • a financial image reader it may be necessary to irradiate IR light and UV light in addition to irradiating visible light of each color of red (R) green (G) blue (B) as a plurality of light sources.
  • R red
  • G green
  • B blue
  • four LEDs are required to increase the amount of UV light. Therefore, there is a demand for a structure in which a maximum of eight LEDs can be arranged.
  • FIG. 15 is an enlarged perspective view showing an incident portion 3a and a light source portion 1 of the light guide body 3 of the lighting device 200a according to the second embodiment.
  • the curved surface portion 12 is composed of a three-stage curved surface, that is, a first curved surface 12a, a second curved surface 12b, and a third curved surface 12c.
  • three LEDs that is, three light sources are arranged side by side in the X direction, which is the long axis direction of the light guide body 3
  • FIG. 16 is a cross-sectional view showing an incident portion 3a of the light guide body 3 of the lighting device 200a according to the second embodiment.
  • FIG. 16 shows a cross section of the incident portion 3a cut by a plane parallel to the XZ plane.
  • the curved surface portion 12 has two discontinuities, that is, a discontinuity point 13 and a discontinuity point 20.
  • the curved surface portion 12 is composed of a first curved surface 12a, a second curved surface 12b, and a third curved surface 12c.
  • the discontinuity point 13 indicates a boundary line between the first curved surface 12a and the second curved surface 12b.
  • the discontinuity point 20 indicates a boundary line between the second curved surface 12b and the third curved surface 12c.
  • each of the first curved surface 12a, the second curved surface 12b, and the third curved surface 12c is a paraboloid.
  • the three light sources arranged in the X direction are the first light source 1a, the second light source 1b, and the third light source 1c from the end side of the light guide body 3. Is. It is desirable that the first light source 1a, the second light source 1b, and the third light source 1c are arranged near the focal points 15a, 15b, and 15c, respectively.
  • 17 (A) to 17 (C) are cross-sectional views showing a range of light guide emission angles at the incident portion 3a of the light guide body 3 of the lighting device 200a according to the second embodiment.
  • the 1a, the second light source 1b, and the third light source 1c are arranged at the focal point 15a, the focal point 15b, and the focal point 15c, respectively, the light emitted in the angular range shown in FIGS.
  • Light emitted from the first light source 1a is since it is reflected by either of the curved surface, light emitted in the range of the angle [psi a in FIG. 17 (A) is guided. Since the light emitted from the second light source 1b is reflected by the second curved surface 12b and the third curved surface 12c to guide the light, the light emitted in the range of the angle ⁇ b in FIG. 17B is guided. do. Since the light emitted from the third light source 1c is reflected by the third curved surface 12c to guide the light, the light emitted in the range of the angle ⁇ c in FIG. 17C is guided.
  • the light guide efficiency of the light emitted from the first light source 1a, the second light source 1b, and the third light source 1c is higher than that in the case where the curved surface portion 12 is composed of one curved surface. Variation can be reduced.
  • the three light sources arranged in the X direction facing the side surface of the light guide body 3 are reflected by three curved surfaces and guided. By illuminating, it becomes possible to reduce the variation in the light guide efficiency between the LEDs arranged in the X direction.
  • the second embodiment is the same as the first embodiment.
  • Embodiment 3 In the first embodiment, an example is described in which the LED substrate 2 on which a plurality of light sources are mounted and the sensor substrate 9 on which the light receiving element portion 8 is mounted are separate components. If the LED substrate 2 and the sensor substrate 9 can be integrated, the cost will be reduced and the assembly will be easy. However, the position of the light guide body 3 in the Z direction is limited by the positional relationship between the imaging optical system 7 and the irradiated body 10. When the LED substrate 2 and the sensor substrate 9 are integrated, the distance between the incident surface 11 and the light emitting surfaces of the plurality of light sources is widened, and the light utilization efficiency is lowered. Therefore, in the third embodiment, the light guide body 3 so that the incident surface 11 of the incident portion 3a of the light guide body 3 protrudes in the ⁇ Z direction from the position of the end portion of the central portion 3b in the ⁇ Z direction. Is formed.
  • FIG. 18 is an enlarged perspective view showing an incident portion 3a and a plurality of light sources of the light guide body 3 of the lighting device 200b according to the third embodiment.
  • the incident portion 3a has a shape in which the incident surface 11 extends in the ⁇ Z direction so that the distance between the incident surface 11 and the light emitting surfaces of the plurality of light sources is minimized, for example, 0.3 mm. With such a shape, it is possible to reduce the amount of light emitted from a plurality of light sources that does not enter the incident surface 11.
  • FIG. 19 is a cross-sectional view showing an incident portion 3a of the light guide body 3 of the lighting device 200b according to the third embodiment.
  • FIG. 19 shows a cross section of the incident portion 3a cut by a plane parallel to the XZ plane.
  • the incident surface 11 protrudes in the ⁇ Z direction by a length J from the end portion of the central portion 3b in the ⁇ Z direction.
  • the length J is, for example, 1 mm.
  • the incident surface 11 and the surface at the end of the central portion 3b in the ⁇ Z direction are connected by a surface 21.
  • the light emitted from the second light source 1b may leak from the surface 21 formed by extending the incident surface 11 in the ⁇ Z direction after being reflected by the second curved surface 12b, and the light guide efficiency may decrease. ..
  • two light sources arranged in the X direction facing the side surface of the light guide body 3 are reflected by two curved surfaces and guided. By illuminating, it becomes possible to reduce the variation in the light guide efficiency between the LEDs arranged in the X direction.
  • two LEDs arranged in the X direction facing the side surface of the light guide body 3 are reflected by two curved surfaces to guide the light. It is possible to reduce variations in light guide efficiency between LEDs arranged in the X direction.
  • the distance between the light emitting surface of the first light source 1a and the second light source 2a and the incident surface 11 of the light guide body 3 can be narrowed, so that the incident surface 11 can be narrowed. It is possible to increase the light incident on the light source. As a result, the efficiency of light utilization is improved.
  • the second embodiment is the same as the first embodiment.
  • 1 light source unit 1a first light source, 1b second light source, 1c third light source, 2 LED substrate, 22 lead wire, 3 light guide body, 3a incident part, 3b central part, 4 scattering surface, 5 holder, 6 Transmitter, 7 Imaging optical system, 8 Light receiving element, 9 Sensor substrate, 10 Irradiated body, 11 Incident surface, 12 Curved surface, 12a 1st curved surface, 12b 2nd curved surface, 12c 3rd curved surface, 100 Image scanner, 200, 200a, 200b lighting device.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Optics & Photonics (AREA)
  • General Physics & Mathematics (AREA)
  • Facsimile Scanning Arrangements (AREA)
  • Light Guides In General And Applications Therefor (AREA)
  • Facsimile Heads (AREA)
  • Planar Illumination Modules (AREA)
PCT/JP2020/015302 2020-04-03 2020-04-03 照明装置及びイメージスキャナ Ceased WO2021199422A1 (ja)

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JP2022511479A JP7341319B2 (ja) 2020-04-03 2020-04-03 照明装置及びイメージスキャナ
PCT/JP2020/015302 WO2021199422A1 (ja) 2020-04-03 2020-04-03 照明装置及びイメージスキャナ
DE112020007020.4T DE112020007020T5 (de) 2020-04-03 2020-04-03 Beleuchtungseinrichtung und bildscanner
US17/912,857 US12248165B2 (en) 2020-04-03 2020-04-03 Illumination device and image scanner
CN202080099118.8A CN115336241B (zh) 2020-04-03 2020-04-03 照明装置以及图像扫描仪

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1093765A (ja) * 1996-07-26 1998-04-10 Canon Inc 導光体及び照明装置及び画像読取装置及び画像読取システム
JPH11313195A (ja) * 1998-02-25 1999-11-09 Rohm Co Ltd 画像読み取り装置
JP2008270885A (ja) * 2007-04-16 2008-11-06 Matsushita Electric Ind Co Ltd 照明装置およびこれを用いた原稿読取り装置

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08101654A (ja) 1994-09-29 1996-04-16 Toshiba Lighting & Technol Corp 照明装置および誘導灯装置
US5839812A (en) * 1995-07-18 1998-11-24 Gl Displays, Inc. Flat parallel light source
US6496285B1 (en) 1998-02-25 2002-12-17 Rohm Co., Ltd. Image reading apparatus
JP4667037B2 (ja) * 2002-06-21 2011-04-06 ウェイヴィーン・インコーポレイテッド マルチランプ照明システム
TW201030284A (en) * 2008-10-30 2010-08-16 Zeon Corp Light source device and liquid cristal display device
US8488216B2 (en) * 2009-02-20 2013-07-16 Nisca Corporation LED light source and image reading apparatus
JP2010193360A (ja) 2009-02-20 2010-09-02 Nisca Corp Ｌｅｄ光源及び画像読取装置
JP5780087B2 (ja) * 2011-09-28 2015-09-16 日本精機株式会社 照明装置
JP5848419B2 (ja) * 2012-03-30 2016-01-27 キヤノン・コンポーネンツ株式会社 イメージセンサユニット、画像読取装置、画像形成装置
JP2015179571A (ja) 2014-03-18 2015-10-08 株式会社東芝 導光体および照明装置
JP2017228440A (ja) 2016-06-23 2017-12-28 スタンレー電気株式会社 車両用信号灯
CN109239965B (zh) * 2018-09-30 2021-11-23 京东方科技集团股份有限公司 一种显示器件及其控制方法
FR3088736B1 (fr) * 2018-11-15 2020-10-30 Thales Sa Dispositif d'eclairage compatible d'equipement(s) de vision nocturne a fenetre d'injection laterale de lumiere diurne et nocturne

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1093765A (ja) * 1996-07-26 1998-04-10 Canon Inc 導光体及び照明装置及び画像読取装置及び画像読取システム
JPH11313195A (ja) * 1998-02-25 1999-11-09 Rohm Co Ltd 画像読み取り装置
JP2008270885A (ja) * 2007-04-16 2008-11-06 Matsushita Electric Ind Co Ltd 照明装置およびこれを用いた原稿読取り装置

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CN115336241A (zh) 2022-11-11
US12248165B2 (en) 2025-03-11

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