JP2014216973A - Imaging unit and imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that, although a technique for directly mounting an imaging chip on a flexible board has also become as known, incident light scatters at a connection where a flexible board and an imaging chip are electrically connected.SOLUTION: There is provided an imaging unit including: an imaging element having an imaging region comprising a plurality of pixels; and a flexible board transmitting output signals from the pixels. The flexible board includes: an opening corresponding to the imaging region and subjected to antireflection processing at a peripheral part; and a folded part where at least a part of the peripheral part is folded in the direction of the imaging region.

Description

  The present invention relates to an imaging unit and an imaging apparatus.

It is known to perform a light shielding process in the imaging unit so that incident light incident on the imaging unit is not scattered and becomes unnecessary light.
[Prior art documents]
[Patent Literature]
[Patent Document 1] JP-A-10-257510

  Recently, the technology of mounting the imaging chip directly on the flexible substrate has been known as the unit has been miniaturized, but along with this, the subject incident at the connection part that electrically connects the flexible substrate and the imaging chip. The problem of light scattering has surfaced.

  The imaging unit according to the first aspect of the present invention includes an imaging element having an imaging region composed of a plurality of pixels, and a flexible substrate that transmits output signals from the plurality of pixels, and the flexible substrate corresponds to the imaging region. , An opening having an antireflection process on the peripheral edge, and a bent part in which at least a part of the peripheral edge is bent in the direction of the imaging region.

  The imaging device in the 2nd aspect of this invention is equipped with said imaging unit.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

It is a disassembled perspective view of the imaging unit concerning this embodiment. It is AA sectional drawing of the imaging unit in FIG. It is sectional drawing of the imaging unit which concerns on other embodiment. It is sectional drawing of the imaging unit which concerns on other embodiment. It is a figure which shows an antireflection process area | region. It is sectional drawing of the imaging device carrying the imaging unit which concerns on this embodiment.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 is an exploded perspective view of the imaging unit 100 according to the present embodiment. The imaging unit 100 mainly includes an imaging element 110, a bump 120, an adhesive frame 130, a flexible substrate 140, a spacer frame 150, and a protective glass 160.

  The imaging element 110 is, for example, a CMOS imaging sensor having an imaging region 111 composed of a plurality of pixels. The subject light passes through the protective glass 160 and forms an image on the imaging region 111. For example, each of 20 million pixels constituting the imaging region 111 outputs an electrical signal corresponding to the amount of received light. An output signal, a control signal, supply power, and the like from each pixel are exchanged with an external circuit via an element terminal 112 provided on the image sensor 110.

  The element terminals 112 are electrically connected to the flexible terminals 141 of the flexible substrate 140 via the bumps 120, respectively. The flexible substrate 140 is further connected to an external circuit board, and an output signal from each pixel is for image processing provided on the external circuit board via a wiring pattern provided on the flexible board 140. Transmitted to the ASIC.

  The adhesive frame 130 constitutes an adhesive layer that adheres the image sensor 110 and the flexible substrate 140. The adhesive frame 130 surrounds the imaging region 111 so as to fill at least a part of the bump 120. That is, the adhesive frame 130 serves as a partition wall that does not hinder subject light incident on the imaging region 111 and prevents moisture, dust, and the like from entering the imaging region 111 from the outside. For the adhesive frame 130, a thermosetting adhesive or the like is used as an adhesive.

  The flexible substrate 140 has an opening 142 at a position corresponding to the imaging region 111. In other words, the opening 142 is provided by cutting away a part of the flexible substrate 140 so as not to block subject light incident on the imaging region 111.

  In particular, in the present embodiment, the flexible substrate 140 is bent such that a part of the periphery of the opening 142 is bent in the direction of the imaging region 111 so that subject light is not scattered on the surface of the bump 120 and becomes stray light. Part 143. The bent portion 143 serves to separate a space connecting the opening 142 and the imaging region 111 from a space where the bump 120 at least a part of which is embedded in the adhesive frame 130 is installed. That is, the bent portion 143 blocks subject light traveling toward the surface of the bump 120. As will be described later, the peripheral portion of the opening 142 is subjected to antireflection processing.

  A spacer frame 150 surrounding the opening 142 is bonded to the surface of the flexible substrate 140 opposite to the surface on which the bonding frame 130 is provided. Further, a protective glass 160 is bonded to the surface of the spacer frame 150 opposite to the surface to which the flexible substrate 140 is bonded so as to close the inside of the frame. In other words, the protective glass 160 closes the opening 142 via the spacer frame 150, thereby forming a sealed space with the imaging region 111.

  The spacer frame 150 plays a role of separating the image sensor 110 and the protective glass 160 at a predetermined interval. By separating the image sensor 110 and the protective glass 160, even if dust adheres to the protective glass 160, the shadow of the dust projected on the imaging region 111 is blurred, so that the influence on image formation can be reduced.

  FIG. 2 is a cross-sectional view taken along the line AA after the imaging unit 100 shown in FIG. 1 is assembled. As illustrated, when the imaging unit 100 is assembled, a sealed space 180 is formed. The sealed space 180 is a space that is surrounded by the adhesive frame 130 and the spacer frame 150 and is closed by the protective glass 160 and that faces the imaging region 111. By sealing the space facing the imaging region 111, entry of moisture, dust and the like from the outside is prevented, and each pixel is protected.

  Further, as shown in the drawing, the bump 120 constitutes a part of the partition so as to be embedded in the adhesive frame 130. Here, if the opening 142 of the flexible substrate 140 is simply cut into a rectangular shape, a part of the subject light that has passed through the protective glass 160 is directed toward the surface of the bump 120, and scattered light may be generated. . Part of the scattered light reaches the imaging region 111 and causes ghosts and the like.

  Therefore, in the present embodiment, as described above, the bent portion 143 is provided on the periphery of the opening 142 of the flexible substrate 140. The bent portion 143 is further bent in the direction parallel to the surface of the imaging region 111 from the tip of the inclined portion 144 and the inclined portion 144 that is obliquely bent in the direction of the imaging region from the periphery of the opening 142 with the bump 120 as a boundary. The parallel part 145 is formed. The parallel part 145 is bonded to the surface of the image sensor 110 via an adhesive 170. The parallel part 145 is not limited to bend in the direction of the imaging region 111 from the tip of the inclined part 144 as shown in the figure, but may be bent in the direction of the bump 120. In this manner, by fixing the tip of the bent portion 143 to the image sensor 110, the flutter of the bent portion 143 can be eliminated, and the occurrence of unexpected scattered light can be suppressed. Further, by providing the inclined portion 144 in the bent portion 143, unnecessary light traveling toward the peripheral portion in the sealed space 180 can be reflected and radiated to the outside.

  FIG. 3 is a cross-sectional view of an imaging unit 200 according to another embodiment. FIG. 3 is a cross-sectional view corresponding to AA in FIG. Elements similar to those in the embodiment of FIG. 1 and FIG.

  In the embodiment of FIG. 1 and FIG. 2, the distance between the imaging region 111 and the protective glass 160 is secured by providing the spacer frame 150. However, if the height of the bump 120 can be set more flexibly, the distance between the imaging region 111 and the protective glass 160 can be secured without providing the spacer frame 150. In this case, the protective glass 160 is bonded to the surface of the flexible substrate 140 so as to directly close the opening 142 of the flexible substrate 140.

  Further, the bent portion 143 of the flexible substrate 140 is configured not to have the parallel portion 145 provided in the embodiment of FIGS. 1 and 2 but to have only the inclined portion 144. If configured in this manner, the surface area of the image sensor 110 corresponding to the parallel portion 145 becomes unnecessary, which is effective when the entire image sensor 110 is downsized. Of course, in the configuration in which the spacer frame 150 is not provided, a configuration in which the bent portion 143 includes the parallel portion 145 may be employed.

  FIG. 4 is a cross-sectional view of an imaging unit 300 according to still another embodiment. 4 is a cross-sectional view corresponding to AA in FIG. 1, similarly to FIG. 3. Elements similar to those in the embodiment of FIG. 1 and FIG.

  In the embodiment of FIGS. 1 and 2, the spacer frame 150 is interposed between the flexible substrate 140 and the protective glass 160 to ensure the distance between the imaging region 111 and the protective glass 160. However, as shown in FIG. 4, the distance between the imaging region 111 and the protective glass 160 can be ensured even when interposed between the imaging element 110 and the flexible substrate 140. In this case, the protective glass 160 is bonded to the surface of the flexible substrate 140 so as to directly close the opening 142 of the flexible substrate 140.

  In the imaging unit 300, the flexible terminal 141 is provided in the parallel part 145 of the bent part 143, and the flexible terminal 141 and the element terminal 112 of the imaging element 110 are electrically connected via the bump 120. Yes. An adhesive 131 is applied around the bump 120. If comprised in this way, while being able to implement | achieve an electrical connection, the flapping of the bending part 143 can be eliminated.

  Next, an antireflection process common to the embodiments described so far will be described. FIG. 5 is a diagram showing an antireflection treatment area. The figure is an exploded perspective view showing a flexible substrate 140 and a protective glass 160 that are common to each embodiment.

  Incident subject light flux can be reflected and scattered by the surfaces of various members to reach the imaging region 111 as unnecessary light. Therefore, it is preferable to apply antireflection processing to a portion where there is a possibility of reflection. As antireflection processing, black coating, flocking paper sticking, surface roughening, engraving of shading lines, etc. can be adopted.

  The peripheral portion 149 of the opening 142 is subjected to antireflection processing. The peripheral portion 149 includes the bent portion 143 described so far. As described above, the bent portion 143 extends from the short side of the rectangular opening 142. However, it is not limited to extending from the short side, but may have a bent portion 146 extending from the long side. In this case, the bent portion 146 is also included in the peripheral portion 149.

  That is, not only the bent portions 143 and 146 but also the peripheral portion 149 including the region facing the protective glass 160 is subjected to antireflection processing. In particular, the outer edge of the peripheral edge 149 is preferably an outer edge corresponding to the protective glass 160. By performing antireflection processing in this manner, unnecessary light that is reflected a plurality of times from the surface of the protective glass 160 can be appropriately attenuated.

  The side surface 161 of the protective glass 160 is subjected to antireflection processing. In this way, by applying antireflection processing to the side surface 161, it is possible to appropriately attenuate unnecessary light that passes through the inner surface and reaches the side surface. In addition, the side surface 161 to which antireflection processing is applied may not be all the side surfaces. When there are a side surface close to the opening 142 and a side surface far from the opening 142, the antireflection processing for the side surface on the far side may be omitted.

  FIG. 6 is a cross-sectional view of a single-lens reflex camera 400 as an example of an imaging apparatus equipped with the imaging unit 100 according to the present embodiment. The image pickup unit to be mounted is not limited to the image pickup unit 100, and any of the image pickup units described in the above-described embodiments may be used, or an image pickup unit in which the respective features are combined.

  The single-lens reflex camera 400 exhibits a function as a camera with the lens unit 500 mounted on the camera body 600. The lens unit 500 includes a plurality of lenses arranged in a lens barrel, and guides an incident subject light beam to the imaging unit 100 of the camera body 600.

  The camera body 600 includes a main mirror 672 and a sub mirror 674. The main mirror 672 is pivotally supported between an oblique position obliquely provided to the subject light beam incident from the lens unit 500 and a retracted position retracted from the subject light beam. The sub mirror 674 is pivotally supported with respect to the main mirror 672 so as to be rotatable.

  When the main mirror 672 is in the oblique position, most of the subject light beam incident through the lens unit 500 is reflected by the main mirror 672 and guided to the focus plate 652. The focus plate 652 is disposed at a position conjugate with the light receiving surface of the image sensor 110 to visualize the subject image formed by the optical system of the lens unit 500. The subject image formed on the focus plate 652 is observed from the viewfinder 650 through the pentaprism 654.

  Part of the subject light beam incident on the main mirror 672 at the oblique position passes through the half mirror region of the main mirror 672 and enters the sub mirror 674. The sub mirror 674 guides a part of the light beam incident from the half mirror region to the focus detection sensor 682. The focus detection sensor 682 outputs the detection result to the CPU 622.

  The focus plate 652, the pentaprism 654, the main mirror 672, and the sub mirror 674 are supported by a mirror box 670 as a structure. The imaging unit 100 is attached to the mirror box 670 via a bracket 684 to which the flexible substrate 140 is fixed. Flexible substrate 140 is electrically connected to body substrate 620.

  Electronic circuits such as a CPU 622 and an image processing ASIC 624 are mounted on the body substrate 620. The output signal of the image sensor 110 is delivered to the image processing ASIC 624 that is a processing chip that processes the output signal via the flexible substrate 140.

  Since each imaging unit described above is mounted on the camera body 600, the camera body 600 may be regarded as an imaging device. The camera body 600 may employ various embodiments. In addition to the above example, a mirrorless type camera body that does not include a mirror unit may be used. The imaging device may be a lens-integrated camera.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

100, 200, 300 Imaging unit, 110 Imaging element, 111 Imaging area, 112 Element terminal, 120 Bump, 130 Adhesive frame, 140 Flexible substrate, 141 Flexible terminal, 142 Opening part, 143, 146 Bent part, 144 Inclined part, 145 Parallel part, 150 Spacer frame, 160 Protective glass, 161 Side surface, 170 Adhesive, 180 Sealed space, 400 Single-lens reflex camera, 500 Lens unit, 600 Camera body, 620 Body substrate, 622 CPU, 624 Image processing ASIC, 650 Finder , 652 Focus plate, 654 Penta prism, 670 Mirror box, 672 Main mirror, 674 Sub mirror, 682 Focus detection sensor, 684 Bracket

Claims (10)

An imaging device having an imaging region composed of a plurality of pixels;
A flexible substrate that transmits output signals from the plurality of pixels,
The flexible substrate is
Corresponding to the imaging region, an opening having an antireflection process on the peripheral edge;
An imaging unit having a bent portion in which at least a part of the peripheral edge portion is bent in the direction of the imaging region. The imaging element and the flexible substrate are electrically connected via bumps,
The imaging unit according to claim 1, wherein the bent portion is bent with the bump as a boundary.   The imaging unit according to claim 2, further comprising an adhesive layer that surrounds the imaging region so as to fill at least a part of the bump and adheres the imaging element and the flexible substrate.   The imaging unit according to any one of claims 1 to 3, further comprising a spacer that contacts the flexible substrate in a region different from the bent portion and separates the imaging element and the flexible substrate.   The imaging unit according to claim 4, wherein the spacer surrounds the imaging area.   The imaging unit according to claim 1, further comprising a protective glass that closes the opening and forms a sealed space with the imaging region.   The imaging unit according to claim 6, wherein at least one side surface of the protective glass is subjected to antireflection processing.   The imaging unit according to claim 6 or 7, wherein the flexible substrate is also subjected to antireflection processing in a region facing the protective glass.   The bent portion is further bent in a direction parallel to a plane on which the imaging region is provided in the direction of the opening that is bent in the direction of the imaging region, and is bonded to the imaging element. Item 9. The imaging unit according to any one of Items 1 to 8.   The imaging device provided with the imaging unit of any one of Claim 1 to 9.

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