JP5800744B2 - Image sensor and reader - Google Patents

Description

  The present invention relates to an image sensor and a reading device.

  Conventionally, a reading device using an image sensor is known as a reading device such as an image scanner, a facsimile, or a copier.

  As such an image sensor, for example, a light receiving element and a frame member disposed so as to surround the light receiving element are provided in the region facing the light receiving surface of the light receiving element, and provided in the opening of the frame member. There are known ones having a fixed lens.

  In the image sensor, the light emitted from the light source is incident on the frame member, and the light incident on the frame member is reflected on the inner wall surface of the frame member or the edge of the lens as reflected light and enters the light receiving element. There is a case. Thereby, a ghost phenomenon that is optical noise may occur. Therefore, in order to reduce the reflected light incident on the light receiving element, an image in which a plurality of uneven light shielding lines formed by virtual lines perpendicular to the first direction connecting the lens and the light receiving element are provided on the inner wall surface of the frame member. A sensor is known (see Patent Document 1).

JP 2010-278501 A

  However, although the conventional image sensor can scatter and reduce the reflected light causing the ghost phenomenon, a plurality of uneven light shielding lines orthogonal to the first direction are formed on the inner wall surface of the frame member. Therefore, the light from the light source may be blocked by the light blocking line. When the light from the light source is blocked by the light blocking line, there is a possibility that the amount of light is insufficient.

The image sensor of the present invention has a light receiving element and a rectangular opening in a region facing the light receiving surface of the light receiving element, and is provided in a frame member surrounding the light receiving element and the opening of the frame member be one having a lens, a, on the inner wall of the frame member, when viewed from the first direction imaginary line forms connecting the said lens said light receiving element, a concave portion or a convex portion is provided, said recess or The convex portion is provided so as to extend along the first direction, and is not provided on the short side of the opening. The image sensor of the present invention has a light receiving element, a rectangular opening in a region facing the light receiving surface of the light receiving element, a frame member surrounding the light receiving element, and an opening of the frame member. A concave portion or a convex portion is provided on the inner wall of the frame member, as viewed from a first direction formed by an imaginary line connecting the lens and the light receiving element, The concave portion or the convex portion is provided so as to extend along the first direction, and is not provided at a corner portion of the opening.

  A reading apparatus according to the present invention includes the above-described image sensor, a light source for supplying light to the image sensor, and a reading medium that reflects light from the light source.

  According to the present invention, it is possible to provide an image sensor that can reduce the possibility that reflected light is supplied to the light receiving element and can reduce the possibility that the amount of light from the light source is insufficient.

(A) is a perspective view which shows schematically the image sensor which concerns on embodiment of this invention, (b) is the II sectional view taken on the line shown to Fig.1 (a). (A) is the II-II sectional view taken on the line shown in Drawing 1 (b), and (b) is a sectional view corresponding to the II-II sectional view showing the modification of an image sensor. (A) is explanatory drawing which shows the incident light in the conventional image sensor, (b) is explanatory drawing which shows the incident light in the image sensor shown in FIG. 1 is a schematic cross-sectional view showing a reading apparatus according to an embodiment of the present invention. (A) is sectional drawing corresponding to the II-II sectional view taken on the line of the image sensor which concerns on other embodiment, (b) is explanatory drawing which shows the incident light in the image sensor shown to (a). (A) is sectional drawing corresponding to the II-II sectional view taken on the line of the image sensor which concerns on other embodiment of this invention, (b) is the II-II sectional view of the image sensor which concerns on other embodiment. It is sectional drawing corresponding to a figure (A) is a perspective view which shows roughly the image sensor which concerns on further another embodiment of this invention, (b) is the III-III sectional view taken on the line shown to Fig.7 (a). (A) is the IV-IV sectional view of the image sensor shown in FIG. 7, (b) is an enlarged plan view which expands and shows a part. (A) is a schematic sectional drawing of the image sensor which concerns on further another embodiment of this invention, (b) is the side view seen from the direction of the arrow shown to Fig.9 (a). (A) is a schematic sectional drawing of the image sensor which concerns on other embodiment of this invention, (b) is the side view seen from the direction of the arrow shown to Fig.10 (a).

<First Embodiment>
Hereinafter, a first embodiment of an image sensor according to the present invention will be described with reference to the drawings. As shown in FIG. 1, the image sensor X <b> 1 has a light receiving element 1 and an opening 2 provided in a region facing the light receiving surface 1 a of the light receiving element 1, and a frame member provided so as to surround the light receiving element 1. 3 and a lens 5 provided in the opening 2. As shown in FIG. 1B, a space is provided between the opening 2 of the frame member 3 and the light receiving element 1, and the space functions as an optical path. Since the light receiving element 1 is disposed below the opening 2, the lens 5 and the light receiving element 1 are disposed in a straight line. Note that D1 shown in the drawing is a direction formed by an imaginary line connecting the lens 5 and the light receiving element 1, and is hereinafter referred to as a first direction D1.

  The light emitted from the light source (not shown) toward the reading medium (not shown) is reflected by the reading medium and is applied to the light receiving element 1 through the lens 5 and the optical path. Then, the light receiving element 1 converts an optical signal into an electrical signal, so that characters, colors, patterns or the like of the reading medium can be read.

The light receiving element 1 has a function of photoelectrically converting the brightness of light emitted from the reading medium into electric charges, and sequentially reads out optical signals and converts them into electrical signals. As the light receiving element 1, a generally known photoelectric conversion element can be used, and for example, a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) can be used.

  The frame member 3 has a function of holding the light receiving element 1 and the lens 5 and can be formed of plastic such as resin. In order to reduce light incident on the frame member 3 from being reflected by the inner wall of the frame member 3, it is preferable to use a black resin as a constituent material of the frame member 3. The frame member 3 is provided so as to surround the light receiving element 1 provided on the bottom surface, and has an opening 2 in a region corresponding to the light receiving surface 1 a of the light receiving element 1.

  The lens 5 has a function of forming an image of the light reflected by the reading medium on the light receiving surface 1 a of the light receiving element 1. As a constituent material of the lens 5, for example, glass, plastic, fluorite, or the like can be used. The lens 5 is provided in an opening 2 provided in a region facing the light receiving surface 1 a of the light receiving element 1. In the present embodiment, the lens 5 has a cylindrical shape, but a rectangular parallelepiped may be used.

The frame member 3 will be described in detail with reference to FIGS. In FIG. 2, the concave portion 7 and the convex portion 9.
The opening 2 in a state where no is provided is indicated by a one-dot chain line, and the lens 5 is indicated by a broken line. Moreover, in FIG. 3, the light which injects into the frame member 3 is shown with the dashed-two dotted line.

  As shown in FIG. 2A, the frame member 3 has an opening 2. The opening 2 has a rectangular shape, and has one long side 2a, the other long side 2b, one short side 2c, and the other short side 2d. And the some recessed part 7 and the some convex part 9 are provided in the inner wall of the frame member 3 so that it may extend in the 1st direction D1. Therefore, when viewed from the first direction D1, a plurality of concave portions 7 and a plurality of convex portions 9 are formed on one long side 2a of the opening 2, the other long side 2b, one short side 2c, and the other short side 2d. Will be provided.

  Specifically, as shown in FIG. 3B, the concave portion 7 and the convex portion 9 provided on the inner wall of the frame member 3 are provided so as to extend in the first direction D1. Therefore, the light emitted from the light source is incident on the frame member 3 and then reflected on the inner wall of the frame member 3.

  Incidentally, in the conventional image sensor shown in FIG. 3A, a plurality of convex portions 9 perpendicular to the first direction D <b> 1 are provided on the inner wall of the frame member 3. Thereby, the possibility that the reflected light is scattered by the convex portion 9 and dispersed in the longitudinal direction D2 or the short direction D3 and supplied to the light receiving element 1 existing in the first direction D1 can be reduced.

  However, in the conventional image sensor shown in FIG. 3A, since a plurality of convex portions 9 perpendicular to the first direction D1 are provided on the inner wall of the frame member 3, the light is supplied to the light receiving element 1. Of the light quantity, there is a possibility that even the peripheral light quantity necessary for the effective reading width is reflected. As a result, the amount of light from the light source is insufficient, so that the signal-to-noise ratio (S / N ratio) of the image sensor is reduced, and the influence of noise on signal transmission is increased. In addition, in order to compensate for the shortage of the light amount from the light source, it is necessary to use a light source with high luminous intensity, and there is a problem that the cost of the image sensor increases.

  On the other hand, the image sensor X1 shown in FIG. 3B is provided with a plurality of concave portions 7 and a plurality of convex portions 9 on the inner wall of the frame member 3 when viewed from the first direction D1, and the plurality of concave portions. Since the seven and the plurality of convex portions 9 are provided so as to extend in the first direction D1, the possibility that the amount of light supplied from the light source is shielded in the first direction D1 can be reduced. Therefore, the possibility that the amount of light from the light source supplied to the light receiving element 1 is insufficient can be reduced. In addition, the peripheral light amount necessary for the effective reading width is not easily shielded in the first direction, and the possibility that the light amount from the light source is insufficient can be reduced. Accordingly, the signal to noise ratio can be increased.

  Further, since the plurality of concave portions 7 and the plurality of convex portions 9 are provided on the inner wall of the frame member 3 when viewed from the first direction D1, the reflected light is scattered in the longitudinal direction D2 or the short direction D3, The possibility that the reflected light is supplied to the light receiving element 1 existing in the first direction D1 can be reduced. That is, the reflected light incident on the frame member 3 is scattered by the plurality of concave portions 7 and the plurality of convex portions 9, and is not scattered by the light receiving element 1 existing in the first direction D <b> 1 and has high intensity. Can be reduced. Thereby, the possibility that the ghost phenomenon occurs can be reduced.

  As described above, the image sensor X1 can reduce the possibility that the reflected light is supplied to the light receiving element 1, and reduce the possibility that the light amount from the light source supplied to the light receiving element 1 is insufficient. it can.

The frame member 3 can be manufactured by filling a predetermined mold with the above-described resin, performing injection molding, and removing the solidified molded body from the mold.

  Here, since the conventional image sensor shown in FIG. 3A is provided with the convex portion 9 orthogonal to the first direction D1, when the injection molding is performed and the molded body is removed from the mold, a plurality of the image sensors are provided. Since the convex portion 7 functions like a wedge, it is necessary to use a mold such as a slide core method. As a result, the cost for manufacturing the mold increases, and the cost of the image sensor may increase.

  On the other hand, the image sensor X1 is provided with a plurality of concave portions 7 and a plurality of convex portions 9 on the inner wall of the frame member 3 when viewed from the first direction D1, and the plurality of concave portions 7 and the plurality of convex portions 9 are provided. Are provided so as to extend in the first direction D1, and when the molded body is removed from the mold by injection molding, the plurality of convex portions 7 and the plurality of concave portions 9 do not function like wedges. . Therefore, it is not necessary to use a slide core type mold, and the increase in cost of the image sensor X1 can be reduced.

  2A shows an example in which the light receiving element 1 is viewed from the direction D1, and the inner wall of the frame member 3 is bent to form the concave portion 7 and the convex portion 9, but the present invention is not limited thereto. It is not something. For example, as illustrated in FIG. 2B, the inner wall of the frame member 3 may be curved to form the concave portion 7 and the convex portion 9. Even in this case, the possibility that the reflected light is supplied to the light receiving element 1 can be reduced, and the possibility that the light amount from the light source is insufficient with respect to the light receiving element 1 can be reduced. Further, by forming the concave portion 7 and the convex portion 9 by bending, it is possible to reduce the possibility of occurrence of burrs when the frame member 3 is pulled out from the mold. In addition, you may combine the curved recessed part 7 and the bent convex part 9, and the curved recessed part 7 and the convex part 9. FIG. Further, only one concave portion 7 may be provided, or only one convex portion 9 may be provided.

  Further, when the light receiving element 1 is viewed from the lens 5 when the light receiving element 1 is viewed from the first direction D1, the concave portion 7 or the convex portion 9 is provided. , One short side 2c and the other short side 2d are not straight but have irregularities.

  A reading device Z including the image sensor X1 according to the first embodiment will be described with reference to FIG.

  The reading device Z includes an image sensor X1, a light source 11 for supplying light to the image sensor X1, and a reading medium P that reflects light from the light source 11. The image sensor X <b> 1 is held by the housing 13, and a cover glass 15 is provided on the surface that contacts the reading medium P. A lid member 17 is provided so as to cover the housing 13 and the cover glass 15.

  The image sensor X1 is held inside the housing 13, and the light source 11 is provided in the vicinity of the upper surface of the image sensor X1. The reading medium P is disposed so as to contact a cover glass 15 provided on the upper surface of the housing 13, and is sandwiched between the cover glass 15 and the lid member 17. The light emitted from the light source 11 is reflected by the reading medium P, and the reflected light is emitted downward. Then, the reflected light supplied to the image sensor X 1 is imaged by the lens 5 and supplied to the light receiving element 1. In this way, the reading device Z can read an image on the reading medium P.

The reading device Z may further include a control unit (not shown) that controls the reading device Z and a drive mechanism (not shown) that drives the image sensor X1. For example, when reading an image or the like, the reading device Z first reads an image or the like of one line having a width corresponding to one pixel in a linear shape. Next, the control unit operates the drive mechanism to read the pixels adjacent to the read one line so that the reading device Z moves on the guide rail (not shown) by one pixel. To work. In FIG. 4, the image sensor X1 is driven in the left direction. Then, the reading device Z reads a reading medium P such as a document at a position to be read. By repeating this operation a plurality of times, the entire reading medium P is read.

  The light source 11 has a function of supplying light to the reading medium P and emitting reflected light from the reading medium P. As the light source 11, an illumination jig such as an LED lamp or an incandescent lamp can be used.

  The housing 13 can be formed of plastic such as resin, like the frame member 3 of the image sensor X1. Also in the housing 13, it is preferable to use a black resin as a forming material of the housing 13 in order to reduce reflection by the inner wall of the housing 13. May be.

  The cover glass 15 is fixed to the housing 13 and has a function of holding the reading medium P disposed on the upper surface of the cover glass 15. In order to allow the light supplied from the light source 11 to reach the reading medium P, it is necessary to have transparency.

  The lid member 17 has a function of sandwiching the reading medium P disposed on the cover glass 15. Further, it has a function of shielding light from outside the reading device Z. As a material for forming the lid member 17, a generally known plastic or the like may be used.

  Although an example in which one light source 11 is provided is shown, the light source may be provided on both sides of the image sensor X1, or a light guide (not shown) may be provided in a direction perpendicular to the paper surface of the drawing. Good.

<Second Embodiment>
The image sensor X2 according to the second embodiment will be described with reference to FIG. The image sensor X2 is provided with a plurality of concave portions 7 and a plurality of convex portions 9 on one long side 2a and the other long side 2b of the opening 2 when viewed from the first direction D1. And the concave part 7 and the convex part 9 are not provided in one short side 2c and the other short side 2d. Further, neither the concave portion 7 nor the convex portion 9 is provided in the corner portion 8 of the opening 2. Other points are the same as those of the image sensor X1 according to the first embodiment, and a description thereof will be omitted. In addition, about the same member, the same code | symbol is attached | subjected and it is the same below.

  In the image sensor X2, a plurality of concave portions 7 and a plurality of convex portions 9 are provided only on one long side 2a and the other long side 2b in the central portion C of the opening 2 in the longitudinal direction D2. The other short side 7c and the other short side 7d, the corner 8 of the opening 2, and the one long side 2a and the other long side 2b at both ends E in the longitudinal direction D2 Further, the projection 9 is not provided.

  As shown in FIG. 5, in the image sensor X <b> 2, the lens 5 is disposed at the upper end portion of the central portion C in the longitudinal direction D <b> 2 of the opening 2. Therefore, the intensity of the light that has passed through the lens 5 is higher in the center portion in the longitudinal direction of the opening 2 than in the end portions E. In other words, the central portion C in the longitudinal direction D2 generates more reflected light having a stronger intensity than both the end portions E. Since the image sensor X2 has the concave portion 7 and the convex portion 9 in the central portion C, the possibility that the reflected light is supplied to the light receiving element 1 can be reduced.

Further, the image sensor X2 is not provided with the concave portion 7 and the convex portion 9 on one long side 2a and the other long side 2b located at both ends E in the longitudinal direction D2 where the amount of reflected light is small. However, since both ends E in the longitudinal direction D2 that are far from the lens 5 generate a small amount of reflected light, the reflected light may be supplied to the light receiving element 1 without providing the concave portion 7 and the convex portion 9. There are few. In addition, since the concave portion 7 and the convex portion 9 are not provided on one short side 2c and the other short side 2d of the opening 2, the frame member 3 can be easily removed from the mold.

  In particular, since the image sensor X2 is not provided with the concave portion 7 and the convex portion 9 at the corner portion 8 of the opening 2, the frame member can be easily formed even at the corner portion 8 having high adhesion between the mold and the frame member 3. 3 can be removed from the mold. Therefore, the image sensor X2 can be easily manufactured.

  A central portion C in the longitudinal direction D2 indicates a portion corresponding to the lens 5 provided above the opening 2, and has a length substantially equal to the diameter of the lens 5. Further, both end portions E in the longitudinal direction D2 indicate regions other than the central portion C.

<Third Embodiment>
An image sensor X3 according to the third embodiment will be described with reference to FIG. In the image sensor X3, in the longitudinal direction D2, a plurality of concave portions 7 are provided over the entire area of one long side 2a and the other long side 2b of the opening 2. Other configurations are the same as those of the image sensor X2, and the description thereof is omitted.

  The image sensor X3 according to the third embodiment has a configuration in which the number of the concave portions 7 provided in the central portion C is larger than the number of the concave portions 7 provided in both end portions E in the longitudinal direction D2. . Accordingly, the possibility that the reflected light is supplied to the light receiving element 1 by the concave portion 7 in the central portion C where the reflected light is likely to be generated can be reduced.

Further, the interval Le between the adjacent recesses 7 provided in the central portion C is shorter than the interval Lc between the adjacent recesses 7 provided in both end portions E. For this reason, in the central portion C where the reflected light is likely to be generated, the interval Lc between the adjacent concave portions 7 of the central portion C is short, so that the reflected light can be efficiently scattered. Furthermore, in the both end portions E where the reflected light is hard to be generated, the interval Le between the adjacent recess portions 7 of the both end portions E is long, so that a large number of the recess portions 7 are not provided. Therefore, the configuration of the frame member 3 can be simplified. Furthermore, since only the concave portion 7 is provided without providing the convex portion 9, the configuration of the frame member 3 can be simplified. Note that the distances Lc and Le between the adjacent recesses 7 indicate the distance between the deepest positions of the recesses 7.

  An image sensor X3 ′ shown in FIG. 6B is a modification of the image sensor X3. The image sensor X3 ′ has a configuration in which the number of the recesses 7 increases from the both ends E toward the center C in the longitudinal direction D2 of the opening 2.

  As described above, the amount of reflected light is the largest at the central portion C in the longitudinal direction D2, and decreases as it goes toward both end portions E. Therefore, the image sensor X3 ′ can scatter reflected light efficiently because the number of the concave portions 7 increases in the longitudinal direction D2 from the both end portions E toward the central portion C. Thereby, possibility that reflected light will be supplied to the light receiving element 1 can be reduced. Moreover, since there are many recessed parts 9 in the center part C with much light quantity, in addition to the said effect, possibility that the light quantity from the light source supplied to the light receiving element 1 is insufficient can be reduced.

  In the third embodiment, an example in which only the concave portion 7 is provided without providing the convex portion 9 is shown, but the concave portion 7 and the convex portion 9 may be provided, or only the convex portion 9 may be provided. Even in that case, the same effect can be obtained.

<Fourth Embodiment>
An image sensor X4 according to the fourth embodiment will be described with reference to FIGS.

  As shown in FIG. 7A, the image sensor X4 is provided with the lens 5 shifted in the lateral direction D3. The number of the concave portions 7 provided on one long side 2 a of the opening 2 is larger than the number of the concave portions 7 provided on the other long side 2 b of the opening 2.

  Here, the lens 5 is attached to the frame member 3 from the short direction D3. In more detail, as shown to Fig.7 (a), it attaches from the frame member upper part 3a. Therefore, as shown in FIG.7 (b), it is hold | maintained and fixed by the frame member lower part 3b. Thereby, the center line 50 of the lens 5 is shifted from the center line 30 of the frame member 3. The center of gravity (center) of the light receiving element 1 is disposed on the center line 50 of the lens 5.

  With such a configuration, the lens 5 can be firmly fixed to the frame member 3, and the lens 5 and the frame member 3 can be easily joined. Further, one of the long sides 2a of the opening 2 near the center line 50 of the lens 5 is supplied with more reflected light than the other long side 2b. However, the image sensor X4 has a configuration in which the number of recesses 7 provided on one long side 2a of the opening 2 is greater than the number of recesses 7 provided on the other long side 2b of the opening 2. Therefore, the reflected light can be efficiently scattered on the one long side 2a side where the reflected light is large. Therefore, the possibility that reflected light is supplied to the light receiving element 1 can be reduced. Similarly to the reflected light, the amount of light on the one long side 7a side is large, but since the concave portion 7 extending in the first direction is provided, the amount of light blocked is reduced, and the light receiving element 1 The possibility that the amount of light is insufficient can be reduced.

  Furthermore, since the center line 50 of the lens 5 and the center of gravity of the light receiving element 1 are provided on the same straight line, the light receiving element 1 can read an image of a reading medium (not shown) without distortion. .

  One long side 2a of the opening 2, the other long side 2b, the one short side 2c, and the concave portion 7 and the convex portion 9 provided on the other short side 2d are one long side 2a of the opening 2. , The other long side 2b, the one short side 2c, and the other short side 2d extending from the other short side 2d in the first direction D1, and actually being provided on the inner wall of the frame member 3. Yes.

<Fifth Embodiment>
An image sensor X5 according to the fifth embodiment will be described with reference to FIG. 9A is a cross-sectional view corresponding to the cross-sectional view taken along the line II of FIG. 1, and FIG. 9B is a side view seen from the light receiving element 1 side indicated by the arrow in FIG. 9A.

  The image sensor X5 is configured such that the distance between the concave portion 7 provided on the light receiving element 1 side and the opening 2 is longer than the distance between the concave portion 7 provided on the lens 5 side and the opening 2. The distance L between the concave portion 7 and the opening 2 becomes longer from the lens 5 side toward the light receiving element 1 side.

  It is preferable that the light receiving element 1 side on which the image formed by the lens 5 appears is easily affected by the reflected light and has a configuration that scatters the reflected light more. The image sensor X5 is configured such that the distance between the concave portion 7 provided on the light receiving element 1 side and the opening 2 is longer than the distance between the concave portion 7 provided on the lens 5 side and the opening 2. In other words, the depth of the concave portion 7 becomes deeper from the lens 5 side toward the light receiving element 1 side.

When the distance L between the concave portion 7 and the opening 2 is long, the angle of the surface formed by the concave portion 7 with respect to the longitudinal direction D2 becomes steep. Thereby, the reflected light can be further scattered by being reflected by the inner wall of the frame member 3 which is a surface formed by the recess 7. Therefore, the reflected light can be efficiently scattered on the light receiving element 1 side, and the influence of the reflected light on the light receiving element 1 can be reduced. Therefore, the signal to noise ratio can be increased.

  Further, since the distance L between the recess 7 and the opening 2 is long on the light receiving element 1 side, the possibility of blocking light from the light source can be further reduced, and a sufficient amount of light is supplied to the light receiving element 1. can do.

  Furthermore, since the distance L between the concave portion 7 and the opening 2 is gradually increased, the light emitted from the light source can be supplied to the light receiving element 1 without being disturbed.

  In the image sensor X5, the distance between the concave portion 7 and the opening 2 is increased at a constant rate. However, the distance may not be increased at a constant rate. For example, the displacement amount of the distance between the recess 7 and the opening 2 may be gradually increased toward the light receiving element 1 side.

<Sixth Embodiment>
An image sensor X6 according to the sixth embodiment will be described with reference to FIG. 10A is a cross-sectional view corresponding to the cross-sectional view taken along the line II of FIG. 1, and FIG. 10B is a side view seen from the light receiving element 1 side indicated by the arrow in FIG.

  The image sensor X6 is the same as the image sensor X5 except that the distance between the concave portion 7 and the opening 2 increases stepwise from the lens 5 side toward the light receiving element 1 side.

  In the image sensor X6, the distance between the recess 7 and the opening 2 is increased in three stages from the lens 5 side toward the light receiving element 1 side. That is, the recesses 7a, 7b, 7c formed by the inner wall of the frame member 3 are stepped. As shown in FIG. 10A, the distances La, Lb, Lc between the recesses 7a, 7b, 7c and the opening 2 with respect to the depths of the recesses 7a, 7b, 7c have a relationship of La> Lb> Lc. Yes.

  As described above, since the distance between the concave portion 7 and the opening 2 is increased stepwise, the concave portion 7 having a long distance between the concave portion 7 and the opening 2 on the light receiving element 1 side where the influence of the reflected light is large is effective. The reflected light can be scattered well.

  In addition, although the example in which the distance between the concave portion 7 and the opening 2 is increased stepwise has been shown, the distance between the concave portion 7 and the opening 2 may be gradually increased and may be increased stepwise. Even in that case, the reflected light can be scattered.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the meaning. The embodiments X1 to X6 may be arbitrarily combined.

  For example, the present invention can also be applied to the case of an image sensor using a lens array in which the lens 5 and the light receiving element 1 are combined as a set, and a plurality of these sets are combined. In that case, a concave portion 7 or a convex portion 9 extending in the first direction formed by an imaginary line connecting the lens 5 and the light receiving element 1 is formed on the inner wall of the frame member 3 that forms an optical path between the lens 5 and the light receiving element 1. do it.

  Although an example of the reading device Z using the image sensor X1 has been described, the reading device Z may be configured by employing any one of the image sensors X2 to X6 instead of the image sensor X1.

X1 to X6 Image sensor Z Reading device P Reading medium 1 Light receiving element 2 Aperture 2a One long side 2b The other long side 2c One short side 2d The other short side 3 Frame member 5 Lens 7 Concave part 9 Convex part 11 Light source 13 Housing Body 15 Cover glass

Claims (10)

A light receiving element;
A frame member that has a rectangular opening in a region facing the light receiving surface of the light receiving element, and is disposed so as to surround the light receiving element;
A lens provided in the opening of the frame member,
A concave portion or a convex portion is provided on the inner wall of the frame member when viewed from a first direction formed by an imaginary line connecting the lens and the light receiving element ,
The image sensor, wherein the concave portion or the convex portion is provided so as to extend along the first direction and is not provided on a short side of the opening . A light receiving element;
A frame member that has a rectangular opening in a region facing the light receiving surface of the light receiving element, and is disposed so as to surround the light receiving element;
A lens provided in the opening of the frame member,
A concave portion or a convex portion is provided on the inner wall of the frame member when viewed from a first direction formed by an imaginary line connecting the lens and the light receiving element,
The concave portion or the convex portion is provided so as to extend along the first direction, and is not provided at a corner portion of the opening. In the longitudinal direction before Symbol openings, the number of the concave portions or the convex portions provided in the center of the opening is larger than the number of the concave portions or the convex portions provided at both ends of the opening, claim The image sensor according to 1 or 2.   The image sensor according to claim 3, wherein in the longitudinal direction of the opening, the number of the concave portions or the convex portions is increased from both end portions toward the central portion. In the longitudinal direction before Symbol openings, spacing of the recesses or between the projections adjacent which is provided in a central portion of said opening, the interval of the concave portion or the convex portions adjacent which is provided at both ends of the opening The image sensor according to claim 1, wherein the image sensor is shorter than the image sensor. The light receiving element is provided below the opening,
The lens is provided displaced in the lateral direction of the opening, the image sensor according to any one of claims 1 to 5. The distance between the recess or the opening and the protruding portion provided on the light-receiving element side is longer than the distance between the opening and the recess or the protrusion provided on the lens side, claims 1 to 6 The image sensor according to any one of the above. The image sensor according to claim 7 , wherein a distance between the concave portion or the convex portion and the opening is gradually increased from the lens side toward the light receiving element side. The image sensor according to claim 7 , wherein a distance between the concave portion or the convex portion and the opening increases stepwise from the lens side toward the light receiving element side. The image sensor according to any one of claims 1 to 9 ,
A light source for supplying light to the image sensor;
And a reading medium that reflects light from the light source.

Images