JP5865675B2 - Image sensor module - Google Patents

Description

  The present invention relates to an image sensor module.

  An image sensor module is widely used to read the contents described in the reading object as image data. In such an image sensor module, linear light extending in the main scanning direction is emitted toward an object to be read, and the reflected light is received by a light receiving means having a photoelectric conversion function such as a sensor IC. For example, a cold cathode tube is used as a light source for generating linear light (see Patent Document 1). White light is emitted from the cold cathode fluorescent lamp. This white light is converted into linear light by a light guide or the like.

  As a request for improving the reading quality of the image sensor module, for example, the color tone of the image of the reading object is read more faithfully and reproduced as image data. In order to realize faithful color reproduction, for example, it is preferable to finely adjust the wavelength spectrum of linear light according to the object to be read and the light receiving means. However, it is very difficult to finely adjust the color tone of light emitted from the cold cathode fluorescent lamp.

JP 2011-164574 A

  The present invention has been conceived under the circumstances described above, and an object of the present invention is to provide an image sensor module capable of reproducing the color of an image of a reading object more faithfully.

  The image sensor module provided by the first aspect of the present invention includes a light emitting unit that emits linear light extending in the main scanning direction toward an object to be read, and a plurality of light receiving units arranged in the main scanning direction. A light receiving means; a lens unit that collects light from the object to be read on the light receiving means; and the light emitting unit, the light receiving means, and a case that houses the lens unit. An LED module having one or more main LED chips that emit light in the main emission wavelength region, a rod-shaped light guide extending in the main scanning direction, and the main emission wavelength when excited by the light in the main emission wavelength region. A main phosphor that emits light in a main fluorescence wavelength region different from the region, and the light guide is a main scan in which light from the LED module is incident An incident surface which is a direction end surface, a reflecting surface extending in the main scanning direction that reflects light traveling in the longitudinal direction from the incident surface, and light traveling from the reflecting surface is emitted as linear light extending in the main scanning direction The light emitting unit emits white linear light by mixing the light in the main light emission wavelength region and the light in the main fluorescence wavelength region, and The plurality of light receiving parts include ones belonging to first to third groups that receive light of first to third wavelength regions different from each other.

  In a preferred embodiment of the present invention, the light receiving means can sequentially perform photoelectric conversion processing with a signal output pause time for each of the first to third groups, and the light emitting unit includes: It is possible to repeat the lighting with the light emission pause time included in the signal output pause time turned off.

  In a preferred embodiment of the present invention, the light emitting unit has auxiliary light means for emitting light in an auxiliary light wavelength region different from both the main light emission wavelength region and the main fluorescence wavelength region.

  In a preferred embodiment of the present invention, the auxiliary light means is an auxiliary phosphor that emits light in the auxiliary light wavelength region when excited by light in the main light emission wavelength region.

  In a preferred embodiment of the present invention, the auxiliary light means is an auxiliary LED chip that emits light in the auxiliary light wavelength region.

  In a preferred embodiment of the present invention, the wavelength spectrum of the linear light from the light emitting unit has a maximum value in the auxiliary light wavelength region.

  In a preferred embodiment of the present invention, the main emission wavelength region is a blue light region, and the main fluorescence wavelength region is a yellow light region.

  In a preferred embodiment of the present invention, the auxiliary light wavelength region is a red light region.

  In a preferred embodiment of the present invention, the light-emitting unit includes two main LED chips.

  In a preferred embodiment of the present invention, each of the main LED chips has a long rectangular shape, and an active layer that is a light emitting portion is disposed closer to one side in the longitudinal direction.

  In a preferred embodiment of the present invention, the two main LED chips are arranged such that their longitudinal directions are parallel to each other and face each other in the short direction, and the active layers of each other are arranged in the longitudinal direction. Are arranged on the opposite side.

  In a preferred embodiment of the present invention, the two main LED chips are arranged in series so that their longitudinal directions coincide with each other.

  In a preferred embodiment of the present invention, the two main LED chips are arranged such that their longitudinal directions are parallel to each other and do not face each other in the lateral direction.

  In a preferred embodiment of the present invention, the two main LED chips can individually emit light.

  In a preferred embodiment of the present invention, the LED module includes an LED case having a recess that houses the one or more main LED chips.

  In a preferred embodiment of the present invention, a translucent resin containing the main phosphor is provided in the recess so as to cover the one or more main LED chips.

  In preferable embodiment of this invention, the said translucent resin has a clearance gap between the said incident surfaces of the said light guide.

  In a preferred embodiment of the present invention, the LED module includes the two main LED chips, and the translucent resin has different thicknesses at portions covering the two main LED chips.

  In a preferred embodiment of the present invention, the LED module has a transparent translucent resin that covers the one or more main LED chips, and the light emitting unit covers the incident surface and includes the main phosphor. It has a phosphor sheet.

  In a preferred embodiment of the present invention, the LED module has a dome-shaped translucent resin that covers the one or more main LED chips and includes the main phosphor, and an incident surface of the light guide. However, it has a concave shape along the translucent resin.

  In a preferred embodiment of the present invention, the first wavelength region is a red light region, the second wavelength region is a green light region, and the third wavelength region is a blue light region.

  In a preferred embodiment of the present invention, the plurality of light receiving units included in the first to third groups are arranged along the main scanning direction for each group and are arranged in parallel to each other. .

  A light-emitting unit provided by the second aspect of the present invention is a light-emitting unit that emits linear light extending in the main scanning direction, and an LED module having one or more main LED chips that emit light in the main light emission wavelength region. And a rod-shaped light guide that extends in the main scanning direction, and a main phosphor that emits light in a main fluorescence wavelength region different from the main emission wavelength region when excited by light in the main emission wavelength region. The light guide includes an incident surface that is an end surface in the main scanning direction on which light from the LED module is incident, and a reflecting surface that extends in the main scanning direction to reflect light traveling in the longitudinal direction from the incident surface. And an emission surface extending in the main scanning direction for emitting light traveling from the reflection surface as linear light extending in the main scanning direction, and the light emitting unit includes the light in the main emission wavelength region and the light It is characterized by emitting a white linear light by mixing the light of the fluorescence wavelength region.

  In a preferred embodiment of the present invention, there is an auxiliary light means for emitting light in an auxiliary light wavelength region different from both the main emission wavelength region and the main fluorescence wavelength region.

  In a preferred embodiment of the present invention, the auxiliary light means is an auxiliary phosphor that emits light in the auxiliary light wavelength region when excited by light in the main light emission wavelength region.

  In a preferred embodiment of the present invention, the auxiliary light means is an auxiliary LED chip that emits light in the auxiliary light wavelength region.

  In a preferred embodiment of the present invention, the wavelength spectrum of the linear light has a maximum value in the auxiliary light wavelength region.

  In a preferred embodiment of the present invention, the main emission wavelength region is a blue light region, and the main fluorescence wavelength region is a yellow light region.

  In a preferred embodiment of the present invention, the auxiliary light wavelength region is a red light region.

  In a preferred embodiment of the present invention, two main LED chips are provided.

  In a preferred embodiment of the present invention, each of the main LED chips has a long rectangular shape, and an active layer that is a light emitting portion is disposed closer to one side in the longitudinal direction.

  In a preferred embodiment of the present invention, the two main LED chips are arranged such that their longitudinal directions are parallel to each other and face each other in the short direction, and the active layers of each other are arranged in the longitudinal direction. Are arranged on the opposite side.

  In a preferred embodiment of the present invention, the two main LED chips are arranged in series so that their longitudinal directions coincide with each other.

  In a preferred embodiment of the present invention, the two main LED chips are arranged such that their longitudinal directions are parallel to each other and do not face each other in the lateral direction.

  In a preferred embodiment of the present invention, the two main LED chips can individually emit light.

  In a preferred embodiment of the present invention, the LED module includes an LED case having a recess that houses the one or more main LED chips.

  In a preferred embodiment of the present invention, a translucent resin containing the main phosphor is provided in the recess so as to cover the one or more main LED chips.

  In preferable embodiment of this invention, the said translucent resin has a clearance gap between the said incident surfaces of the said light guide.

  In a preferred embodiment of the present invention, the LED module includes the two main LED chips, and the translucent resin has different thicknesses at portions covering the two main LED chips.

  In a preferred embodiment of the present invention, the LED module has a transparent translucent resin that covers the one or more main LED chips, and the light emitting unit covers the incident surface and includes the main phosphor. It has a phosphor sheet.

  In a preferred embodiment of the present invention, the LED module has a dome-shaped translucent resin that covers the one or more main LED chips and includes the main phosphor, and an incident surface of the light guide. However, it has a concave shape along the translucent resin.

  According to such a configuration, in the light emitting unit, white light can be appropriately emitted by mixing the light in the main emission wavelength region and the light in the main fluorescence wavelength region. Since the light receiving means can individually receive the light in the first to third wavelength regions, so-called full color reading can be performed by irradiating the reading object with white light. Therefore, the color of the image described in the reading object can be reproduced more faithfully.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

It is a top view which shows an example of the image sensor module which concerns on this invention. It is a bottom view which shows the image sensor module of FIG. It is sectional drawing which follows the III-III line of FIG. It is a front view which shows the light emission unit used for the image sensor module of FIG. It is a principal part front view which shows the LED module used for the light emission unit of FIG. It is a principal part enlarged front view which shows the LED module of FIG. It is a rear view which shows the LED module of FIG. It is a side view which shows the LED module of FIG. It is principal part sectional drawing in alignment with the IX-IX line of FIG. 5 of the light emission unit of FIG. It is a principal part top view which shows sensor IC used for the image sensor module of FIG. It is sectional drawing which follows the XI-XI line of FIG. 3 is a timing chart showing image reading processing using the image sensor module of FIG. 1. It is a graph which shows the wavelength spectrum of the image sensor module as a reference example. It is a graph which shows the wavelength spectrum of the image sensor module of FIG. It is a principal part enlarged front view which shows the modification of the LED module of FIG. It is a principal part enlarged front view which shows the other modification of the LED module of FIG. It is a principal part enlarged front view which shows the other modification of the LED module of FIG. It is a principal part enlarged front view which shows the other modification of the LED module of FIG. It is principal part sectional drawing which shows the modification of the light emission unit of FIG. 5 and FIG. It is principal part sectional drawing which shows the other modification of the light emission unit of FIG. 5 and FIG.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

  1 to 3 show an example of an image sensor module according to the present invention. The image sensor module 101 of this embodiment includes a case 200, a substrate 300, a light emitting unit 400, a lens unit 500, and a sensor IC 600. The image sensor module 101 is used for reading an image of a reading object as image data by being incorporated in a scanner, for example.

  The case 200 constitutes the outer shape of the image sensor module 101 and accommodates other components. The case 200 extends long in the main scanning direction x, and has a cross-sectional shape defined by the sub scanning direction y and the thickness direction z (a direction perpendicular to both the main scanning direction x and the sub scanning direction y). Is generally rectangular. Examples of the material of the case 200 include a liquid crystal polymer resin.

  The substrate 300 has a long rectangular shape in which the main scanning direction x is the longitudinal direction and the sub-scanning direction y is the width direction, and is made of, for example, glass epoxy resin or ceramics. A sensor IC 600 is mounted on the substrate 300, and the light emitting unit 400 is connected thereto. In addition, a connector for connecting the image sensor module 101 to the scanner or the like is attached to the substrate 300.

  As shown in FIGS. 4 and 9, the light emitting unit 400 includes an LED module 410, a light guide 460, and a light guide case 465, and is configured to emit white linear light.

  As shown in FIGS. 5 to 9, the LED module 410 includes a lead 420, an LED case 430, two LED chips 441, two zener diodes 445, and a translucent resin 450. In FIGS. 5 and 6, the translucent resin 450 is omitted for convenience of understanding.

  The lead 420 is for supporting the two LED chips 441 and the two Zener diodes 445 and for passing a current through them, and is made of a metal such as a Cu alloy. The lead 420 has a die bonding part 421 and a plurality of terminal parts 422. The die bonding part 421 is located at substantially the center of the lead 420, and two LED chips 441 and two Zener diodes 445 are die-bonded. The plurality of terminal portions 422 extend from the LED case 430 downward in the thickness direction z, and are used to attach the LED module 410 (light emitting unit 400) to the substrate 300. The LED case 430 has a substantially rectangular shape, and is made of, for example, a white resin. The LED case 430 partially covers the lead 420. A concave portion 431 is formed in the LED case 430. The concave portion 431 has a circular shape that exposes the die bonding portion 421.

  The two LED chips 441 correspond to the main LED chip in the present invention, and are die-bonded to the die bonding portion 421 with, for example, an insulating resin paste. 5 and 6, the center line in the emission direction of the linear light of the light emitting unit 400 is indicated by a one-dot chain line. In the present embodiment, the two LED chips 441 are arranged with the emission direction center line interposed therebetween. Each LED chip 441 has a long rectangular shape and is configured as a so-called two-wire type. The LED chip 441 is connected to the lead 420 via a wire. The LED chip 441 has, for example, an n-type semiconductor layer made of a GaN-based semiconductor, a p-type semiconductor layer, and an active layer sandwiched between them, and emits blue light. That is, in the present embodiment, the main emission wavelength region referred to in the present invention is a blue light region. A hatched portion in FIG. 6 is a portion where the active layer is present. As clearly shown in the figure, the two LED chips 441 are in a posture in which their longitudinal directions are parallel to each other. Furthermore, the active layers of each other are located on the same side in the longitudinal direction. The two LED chips 441 can emit light individually.

  The two Zener diodes 445 are for avoiding electrostatic breakdown of the two LED chips 441, and are die-bonded to the die bonding portion 421 using, for example, Ag paste. Each zener diode 445 is connected to a portion of the lead 420 other than the die bonding portion 421 through a wire.

  As shown in FIG. 9, the translucent resin 450 is formed in the recess 431 of the LED case 430 so as to cover the two LED chips 441 and the two Zener diodes 445 and a plurality of wires connected thereto. Yes. The translucent resin 450 is made of a material in which a main phosphor is mixed in a transparent silicone resin such as methyl or dimethyl. This main phosphor emits yellow light when excited by blue light from the LED chip 441. That is, in this embodiment, the light in the main fluorescence wavelength region is yellow light. Thereby, the LED module 410 emits white light obtained by mixing blue light and yellow light. Furthermore, for example, titanium oxide may be mixed in the light-transmitting resin 450 for the purpose of light diffusion. In the present embodiment, the surface of the translucent resin 450 is slightly recessed with respect to the surface of the LED case 430. Further, a portion of the translucent resin 450 that covers one LED chip 441 and a portion that covers the other LED chip 441 have different thicknesses in the main scanning direction x.

  Further, in the present embodiment, the translucent resin 450 includes an auxiliary phosphor. This auxiliary phosphor emits auxiliary fluorescence that is different from yellow light as main fluorescence when excited by blue light. In the present embodiment, this auxiliary fluorescence is red light.

  The light guide 460 has a rod shape extending in the main scanning direction x, and is made of, for example, an acrylic resin typified by a transparent PMMA resin. As shown in FIGS. 3 and 9, the light guide 460 has an incident surface 461, a reflecting surface 462, and an exit surface 463. The incident surface 461 is one end surface of the light guide 460 in the main scanning direction x and faces the LED chip 441 of the LED module 410. In the present embodiment, a gap is provided between the incident surface 461 and the translucent resin 450. The reflection surface 462 extends long in the main scanning direction x, and reflects the light that has traveled through the light guide 460 after being incident from the incident surface 461 toward the upper left in FIG. The reflecting surface 462 has a configuration in which, for example, a plurality of grooves are densely arranged in the main scanning direction x. The emission surface 463 extends long in the main scanning direction x, and emits the light reflected by the reflection surface 462 as linear light extending in the main scanning direction x.

  The light guide case 465 is for fixing the light guide 460 to the LED module 410 and preventing light from leaking from the light guide 460. The light guide case 465 is made of, for example, a white resin, and has a shape that substantially surrounds the portion of the light guide 460 on the side where the reflection surface 462 is formed, as shown in FIG. Moreover, the part attached to LED module 410 among the light guide case 465 is made into the substantially rectangular plate shape.

  The lens unit 500 condenses the light that has traveled in the thickness direction z from the object to be read on the sensor IC 600 at an equal magnification. The lens unit 500 includes a plurality of lenses 510 and a lens holder 520. The plurality of lenses 510 have respective optical axes along the thickness direction z and are arranged in the main scanning direction x. The lens holder 520 is made of an opaque resin and holds a plurality of lenses 510.

  The sensor IC 600 is an example of the light receiving means referred to in the present invention, and is mounted on the substrate 300. As shown in FIGS. 10 and 11, the sensor IC 600 includes a plurality of light receiving units 610 and a plurality of filters 620.

  The plurality of filters 620 includes a first filter 621, a second filter 622, and a third filter 623. These first to third filters 621, 622, and 623 each have a strip shape extending in the main scanning direction x, and are arranged in parallel to each other with an interval in the sub-scanning direction y. In the present embodiment, the first filter 621 selectively transmits red light and attenuates visible light other than red light. The second filter 622 selectively transmits green light and attenuates visible light other than green light. The third filter 623 selectively transmits blue light and attenuates visible light other than blue light.

  The plurality of light receiving units 610 are divided into a first group 611, a second group 612, and a third group 613. Each of the first to third groups 611, 612, and 613 is arranged along the main scanning direction x. The first to third groups 611, 612, and 613 are arranged in parallel to each other with an interval in the sub-scanning direction y. The first group 611 is covered with the first filter 621, the second group 612 is covered with the second filter 622, and the third group 613 is covered with the third filter 623.

  The light collected by the lens unit 500 passes through the first to third filters 621, 622, 623 and is received by the first to third groups 611, 612, 613. The first group 611 receives the red component of the collected light, the second group 612 receives the green component of the collected light, and the third group 613 receives the blue component of the collected light. Is received. The sensor IC 600 has, for example, a photoelectric conversion function for outputting an electric signal having a strength corresponding to the intensity of received light from the pad 630 for each of the first group 611, the second group 612, and the third group 613.

  FIG. 12 shows a timing chart of image reading processing using the image sensor module 101. The signal LED in the figure indicates that the LED chip 441 of the LED module 410 is lit when in the Hi state. The signal CLK is a so-called clock signal, and one pulse defines reading of one pixel. The signal Ao indicates the timing at which the image data read by the image sensor module 101 is output as an analog signal, and is output to, for example, the scanner side in the Hi state.

  First, the signal LED becomes Hi during the period DrR, and white linear light is emitted from the light emitting unit 400. In this period DrR, the photoelectric conversion processing for red light is performed by the light receiving units 610 of the sensor IC 600 belonging to the first group 611. This photoelectric conversion process is for one column along the main scanning direction x. The signals for one column are collectively output as analog signals to the scanner in the period AoR after the period DrR.

  Next, the period DrG starts after a predetermined emission stop time has elapsed from the end of the period DrR. In the period DrG, white linear light is emitted again from the light emitting unit 400, and photoelectric conversion processing for green light is performed by the light receiving units 610 of the sensor IC 600 belonging to the second group 612. This green light signal is output as a batch of analog signals to the scanner in a period AoG that starts after a predetermined signal output pause time after the end of the period AoR after the period DrR.

  Furthermore, the period DrB starts after a predetermined emission pause time has elapsed from the end of the period DrG. In the period DrB, white linear light is emitted again from the light emitting unit 400, and the photoelectric conversion processing for blue light is performed by the light receiving units 610 of the sensor IC 600 belonging to the third group 613. This blue light signal is output as a batch of analog signals to the scanner in a period AoB that starts after the end of the period AoG and after a predetermined signal output pause time after the period DrB. With these processes, reading of image data for red light, green light, and blue light is completed for one column in the main scanning direction x. By sequentially executing these processes along the sub-scanning direction y, the reading process can be performed on the entire surface of the reading object. In the above processing, the light emission pause time is generally set shorter than the signal output pause time, and is the same as the signal output pause time at the longest.

  Next, the operation of the image sensor module 101 will be described.

  According to the present embodiment, in the light emitting unit 400, white light can be appropriately emitted by mixing blue light as light in the main emission wavelength region and yellow light as light in the main fluorescence wavelength region. . Since the sensor IC 600 can individually receive red light, blue light, and green light, so-called full color reading can be performed by irradiating the reading object with white light. Therefore, the color of the image described in the reading object can be reproduced more faithfully.

  In the present embodiment, an auxiliary phosphor that emits red light as auxiliary fluorescence is employed. Thereby, the wavelength spectrum of the white light emitted from the light emitting unit 400 can be made suitable for more faithful color reproduction. For example, FIG. 13 shows a wavelength spectrum of outgoing light when blue light is used as light in the main emission wavelength region and yellow light is used as light in the main fluorescence wavelength region. On the other hand, FIG. 14 is a wavelength spectrum of light emitted from the light emitting unit 400 of the present embodiment. When both are compared, in the wavelength spectrum shown in FIG. 14, a maximum value is recognized in a wavelength region including 620 nm. This wavelength region is a so-called red region, and it is recognized that the intensity of the red region is enhanced by employing an auxiliary phosphor that emits red light. The light having such a wavelength spectrum is suitable for further improving the color reproducibility as compared with the light having the wavelength spectrum shown in FIG.

  As described with reference to FIG. 12, in the present embodiment, in the reading process of the reading object, the LED module 410 is turned on only at a necessary timing, and is turned off at an unnecessary timing. It is not always lit. As a result, power saving of the light emitting unit 400, and hence the image sensor module 101, can be achieved.

  By providing the two LED chips 441 that can be individually lit, it is possible to realize a usage mode in which only one LED chip 441 is lit according to the amount of light required for reading. This can appropriately set the brightness at the time of reading and contributes to power saving.

  By providing a gap between the translucent resin 450 and the incident surface 461, for example, it is possible to suppress color variations caused by only a part of the translucent resin 450 coming into contact with the incident surface 461. In particular, since the LED chip 441 generates heat during light emission, thermal expansion of the translucent resin 450 is expected. By providing the gap, even if the translucent resin 450 is thermally expanded, the entire translucent resin 450 can be kept away from the incident surface 461.

  The portions of the translucent resin 450 that cover the two LED chips 441 have different thicknesses, so that the amount of fluorescence excited by the light of one LED chip 441 and the light of the other LED chip 441 are excited. The amount of fluorescent light is different. Thereby, the wavelength spectrums of the white light emitted from the vicinity of the two LED chips 441 are different from each other. For this reason, it is possible to emit white light having different wavelength spectra in a state in which only one LED chip 441 is lit, a state in which only the other LED chip 441 is lit, and a state in which both LED chips 441 are lit. . Therefore, more detailed color reproduction can be performed.

  15 to 20 show modified examples of each part of the image sensor module 101. In these drawings, the same or similar elements as those in the above embodiment are denoted by the same reference numerals as those in the above embodiment.

  FIG. 15 shows a modification of the LED module 410. In this modification, the two LED chips 441 are arranged such that the active layers of the two LED chips 441 are located on the opposite sides in the respective longitudinal directions. According to such a configuration, it is possible to prevent the active layers of the two LED chips 441 from absorbing light emitted from each other. The portion where the active layer is provided (shaded portion in FIG. 15) is a portion where the height from the lead 420 is higher than the surroundings. Avoiding adjacent portions is suitable for suppressing light absorption.

  FIG. 16 shows another modification of the LED module 410. In the present modification, the two LED chips 441 are arranged in series so that their longitudinal directions coincide with each other. Even with such a configuration, the LED chips 441 can be prevented from absorbing each other's light.

  FIG. 17 shows another modification of the LED module 410. In this modification, the two LED chips 441 are arranged so as not to overlap each other in the respective longitudinal directions, and are not opposed to each other in the respective lateral directions. Even with such a configuration, the LED chips 441 can be prevented from absorbing each other's light.

  FIG. 18 shows another modification of the LED module 410. In this modification, in addition to the configuration shown in FIG. 6, an LED chip 442 is added. The LED chip 442 corresponds to the auxiliary LED chip in the present invention, and emits, for example, red light as light in the auxiliary light wavelength region. According to such a configuration, the wavelength spectrum of the white light emitted from the LED module 410 (light emitting unit 400) can have a higher relative intensity in the red light region. Thereby, the color reproducibility can be further enhanced. Further, as understood from FIGS. 5 and 18, the LED chip 442 can emit light independently of the two LED chips 441. For example, a method of arbitrarily adjusting the wavelength spectrum of white light emitted from the light emitting unit 400 by controlling the current flowing through the LED chip 442 can be realized.

  FIG. 19 shows a modification of the light emitting unit 400. In this modification, the translucent resin 450 is made of only a transparent resin and does not contain a phosphor. The light emitting unit 400 of this modification includes a phosphor sheet 451. The phosphor sheet 451 is a sheet containing a main phosphor and an auxiliary phosphor as referred to in the present invention and containing a resin as a main component. The phosphor sheet 451 is attached to, for example, the incident surface 461 of the light guide 460 and covers the concave portion 431 of the LED module 410. In this modification, the translucent resin 450 has a dome shape large enough to cover the two LED chips 441 and the two Zener diodes 445, and may not fill the entire interior of the recess 431. . According to such a configuration, the distance from the two LED chips 441 to the phosphor sheet 451 can be determined relatively accurately. Thereby, the color mixing ratio of the blue light from the LED chip 441, the yellow light from the phosphor sheet 451, and further the red light can be made closer to a desired ratio.

  FIG. 20 shows another modification of the light emitting unit 400. In this modification, the above-described main fluorescent material and further the translucent resin 450 including the auxiliary fluorescent material are formed in a dome shape. The incident surface 461 of the light guide 460 is a concave surface along the translucent resin 450. The translucent resin 450 is accommodated in the incident surface 461 with a slight gap from the incident surface 461. According to such a configuration, the light guide 460 and the lead 420 of the LED module 410 can be brought closer to each other, and the dimension of the light emitting unit 400 in the main scanning direction x is shortened without changing the reading length. can do.

  The image sensor module according to the present invention is not limited to the above-described embodiment. The specific configuration of each part of the image sensor module according to the present invention can be varied in design in various ways.

101 Image sensor module 200 Case 300 Substrate 400 Light emitting unit 410 LED module 420 Lead 421 Die bonding part 422 Terminal part 430 LED case 431 Recess 441 (Main) LED chip 443 Active layer 442 (Auxiliary) LED chip 445 Zener diode 450 Translucent resin 451 Phosphor sheet 460 Light guide 461 Entrance surface 462 Reflection surface 463 Output surface 465 Light guide case 500 Lens unit 510 Lens 520 Lens holder 600 Sensor IC (light receiving means)
610 Light receiver 611 First group 612 Second group 613 Third group 620 Filter 621 First filter 622 Second filter 623 Third filter 630 Pad x main scanning direction y sub-scanning direction z thickness direction

Claims (19)

A light emitting unit that emits linear light extending in the main scanning direction toward the reading object;
A light receiving means having a plurality of light receiving portions arranged in the main scanning direction;
A lens unit for condensing the light from the reading object on the light receiving means;
A case for housing the light emitting unit, the light receiving means, and the lens unit;
The light-emitting unit emits light in the main light emission wavelength region, has an elongated rectangular shape, and has an LED module having two main LED chips in which an active layer that is a light-emitting portion is disposed closer to one side in the longitudinal direction; An elongated rod-shaped light guide, and a main phosphor that emits light in a main fluorescence wavelength region different from the main emission wavelength region by being excited by light in the main emission wavelength region,
The light guide includes an incident surface that is an end surface in the main scanning direction on which light from the LED module is incident, a reflecting surface that extends in the main scanning direction to reflect light traveling in the longitudinal direction from the incident surface, and the reflection A light exiting surface extending in the main scanning direction for emitting light traveling from the surface as linear light extending in the main scanning direction;
The light emitting unit emits white linear light by mixing light in the main emission wavelength region and light in the main fluorescence wavelength region,
The plurality of light receiving portions, viewed contains a belonging to the first to third group receives light of different first, second, and third wavelength regions to each other,
The image sensor module, wherein the two main LED chips are arranged in series so that their longitudinal directions coincide with each other . A light emitting unit that emits linear light extending in the main scanning direction toward the reading object;
A light receiving means having a plurality of light receiving portions arranged in the main scanning direction;
A lens unit for condensing the light from the reading object on the light receiving means;
A case for housing the light emitting unit, the light receiving means, and the lens unit;
The light-emitting unit emits light in the main light emission wavelength region, has an elongated rectangular shape, and has an LED module having two main LED chips in which an active layer that is a light-emitting portion is disposed closer to one side in the longitudinal direction; An elongated rod-shaped light guide, and a main phosphor that emits light in a main fluorescence wavelength region different from the main emission wavelength region by being excited by light in the main emission wavelength region,
The light guide includes an incident surface that is an end surface in the main scanning direction on which light from the LED module is incident, a reflecting surface that extends in the main scanning direction to reflect light traveling in the longitudinal direction from the incident surface, and the reflection A light exiting surface extending in the main scanning direction for emitting light traveling from the surface as linear light extending in the main scanning direction;
The light emitting unit emits white linear light by mixing light in the main emission wavelength region and light in the main fluorescence wavelength region,
The plurality of light receiving units include those belonging to first to third groups that receive light in different first to third wavelength regions,
2. The image sensor module according to claim 2, wherein the two main LED chips are arranged so that their longitudinal directions are parallel to each other and do not face each other in the short direction. The light receiving means is capable of sequentially performing photoelectric conversion processing for each of the first to third groups with a signal output pause time in between.
3. The image sensor module according to claim 1, wherein the light emitting unit can be repeatedly turned on with the light emission during the light emission stop time included in the signal output stop time interposed therebetween. 4. The image sensor module according to claim 1, wherein the light emitting unit includes auxiliary light means that emits light in an auxiliary light wavelength region different from both the main light emission wavelength region and the main fluorescence wavelength region. 5. The image sensor module according to claim 4 , wherein the auxiliary light means is an auxiliary phosphor that emits light in the auxiliary light wavelength region when excited by light in the main light emission wavelength region. The image sensor module according to claim 4 , wherein the auxiliary light means is an auxiliary LED chip that emits light in the auxiliary light wavelength region. The wavelength spectrum of the linear light from the light emitting unit has a maximum in the auxiliary light wavelength region, the image sensor module according to any one of claims 4 to 6. The main emission wavelength region is a blue light region, the main fluorescence wavelength region is a yellow light region, the image sensor module according to any one of claims 4 to 7. The image sensor module according to claim 8 , wherein the auxiliary light wavelength region is a red light region. The two main LED chips are arranged such that their longitudinal directions are parallel to each other and face each other in the short direction, and the active layers of each other are arranged on opposite sides in the longitudinal direction. Item 10. The image sensor module according to any one of Items 1 to 9 . The two main LED chip is a separately capable of emitting light, the image sensor module according to any one of claims 1 to 10. The image sensor module according to any one of claims 1 to 11 , wherein the LED module includes an LED case having a recess for accommodating the two main LED chips. The image sensor module according to claim 12 , wherein a light-transmitting resin including the main phosphor is provided in the recess so as to cover the two main LED chips. The image sensor module according to claim 13 , wherein the translucent resin has a gap between the light guide and the incident surface. Upper KiToruhikari resin, the thickness of the portion covering the two main LED chips are different from each other, the image sensor module according to claim 14. The LED module has a transparent translucent resin that covers the two main LED chips,
The light emitting unit covers the entrance surface has a phosphor sheet comprising the main phosphor, an image sensor module according to any one of claims 1 to 12. The LED module has a dome-shaped translucent resin that covers the two main LED chips and includes the main phosphor.
The incident surface of the light guide body, the along the light-transmitting resin is a concave, image sensor module according to any one of claims 1 to 12. The first wavelength region is a red light region, the second wavelength region is a green light region, the third wavelength region is a blue light region, the image sensor module according to any one of claims 1 to 17 . The image sensor module according to claim 18 , wherein the plurality of light receiving units included in the first to third groups are arranged along the main scanning direction for each of the groups and are arranged in parallel to each other. .