JP5326904B2 - Lens barrel - Google Patents

Description

  The present invention relates to a lens barrel having an image sensor.

  2. Description of the Related Art In recent years, an image pickup apparatus has been widely used in which incident light from a lens is picked up using an image pickup device such as a charge coupled device (hereinafter abbreviated as CCD), converted into an electric signal, and taken out as an image. Yes. In addition, along with demands for miniaturization and high performance of portable devices such as DSC (Digital Still Camera) and camera-equipped mobile phones, there is a further demand for miniaturization and weight reduction of lens barrels, which are the main components of imaging devices. ing.

  Conventionally, the entry of dust and the like from the outside is prevented between the image sensor that constitutes the lens barrel and an optical filter made of a glass plate material that shields light of a specific wavelength such as infrared rays and transmits visible light. For this purpose, an elastic member made of rubber or the like is sandwiched and held by the holding member. In the case of such a holding structure, a distance for sandwiching the elastic member is necessary, which is a factor that hinders the thinning of the lens barrel portion (reducing the thickness of the main body in the optical axis direction).

  On the other hand, in Patent Document 1, the imaging element is configured as a rectangular plate-shaped bare chip having an imaging surface. In addition, the imaging element is disposed on the bottom wall of the housing recess provided in the package, and a glass plate is bonded to the front surface of the package housing so as to cover the housing recess.

JP 2006-227103 A

  However, in the lens barrel of Patent Document 1, when placed in a high temperature environment exceeding about 60 ° C., a gas containing an organic component that is an adhesive material from an adhesive that fixes the glass plate and the package housing. In some cases, an organic component adheres to a surface of the image sensor or a glass plate facing the image sensor. When incident light from the lens passes through a portion to which an organic component is attached, light absorption and scattering occur at that portion. For this reason, the luminous flux of the incident light that reaches the image sensor locally increases and decreases as compared to when it passes through the lens. Therefore, there is a problem that unintended brightness and darkness occur in the captured image and the image quality deteriorates.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a lens barrel that is thinned while ensuring the quality of an image captured by an image sensor.

  In order to achieve the above-described object, the lens barrel of the present invention includes an image sensor that converts incident light into an electrical signal, and an optical filter, and the optical filter is disposed to face the incident surface of the image sensor. At least a part of the image sensor is bonded to the imaging element by an adhesive member.

  According to such a configuration, even if a gas containing an organic component is generated from the adhesive member, the gas is vented to the outside from the gap where the adhesive member between the optical filter and the imaging element is not interposed. Accordingly, it is possible to provide a lens barrel that is thin while ensuring the quality of an image captured by the image sensor.

  In addition, a light shielding member is provided between the imaging element and the optical filter, and at least a part of a surface of the light shielding member facing the imaging element is bonded to the imaging element by the first adhesive member, and the optical filter of the light shielding member At least a part of the opposing surface may be bonded to the optical filter by the second adhesive member.

  According to such a configuration, it is possible to reduce the thickness of the lens barrel even if a light shielding member for further improving image quality is provided.

  Further, the adhesive strength between the light shielding member by the first adhesive member and the imaging element may be higher than the adhesive strength between the light shielding member by the second adhesive member and the optical filter.

  According to such a configuration, when the optical filter is misaligned during the production of the lens barrel, the optical filter having a low adhesive strength with the light shielding member can be easily peeled and repaired.

  Further, the outer shape of the light shielding member may be larger than the outer shape of the optical filter.

  According to such a configuration, when the optical filter is misaligned during the production of the lens barrel, the portion where the light shielding member extends outward from the optical filter can be held by a jig or the like. Therefore, the light shielding member and the optical filter can be easily peeled off and repaired.

  Further, when the outer shape of the light shielding member is larger than the outer shape of the optical filter, the adhesive strength between the light shielding member by the first adhesive member and the imaging element is greater than the adhesive strength between the light shielding member by the second adhesive member and the optical filter. It may be low.

  According to such a configuration, the light shielding member and the optical filter can be further easily peeled and repaired.

  According to the present invention, the lens barrel can be thinned while ensuring the quality of an image picked up by the image pickup device.

FIG. 3 is an exploded perspective view of the lens barrel in the first embodiment. It is a front view of the light incident surface side of the imaging unit. FIG. 3 is a schematic cross-sectional view taken along the line A-A ′ of the imaging unit in FIG. 2. 6 is an exploded perspective view of a lens barrel in Embodiment 2. FIG. It is a front view of the light incident surface side of the imaging unit. FIG. 6 is a schematic cross-sectional view taken along the line A-A ′ of the imaging unit in FIG. 5. 10 is an exploded perspective view of a lens barrel in Embodiment 3. FIG. It is an expansion disassembled perspective view of the imaging part. It is a front view of the light incident surface side of the imaging unit. FIG. 10 is a schematic cross-sectional view taken along the line A-A ′ of the imaging unit in FIG. 9.

  Hereinafter, description will be given with reference to the drawings.

(Embodiment 1)
FIG. 1 is an exploded perspective view of a lens barrel 100 in the first embodiment. The lens barrel 100 includes a lens unit 110, an imaging unit 120, and a plurality of screws 125.

  The lens unit 110 has a plurality of lenses (not shown) for imaging incident light on the image sensor 123, and each lens is a lens frame (not shown) made of a resin molded member. Is retained. The lens frame is retracted and accommodated in a lens fixing frame 111 that is fixed to the master flange 112 during non-imaging. On the other hand, at the time of imaging, it can be driven by a DC motor 113 that is an actuator and can be extended from the lens fixing frame 111 to perform a zoom operation.

  The imaging unit 120 includes an imaging element 123 that converts incident light into an electrical signal. The image pickup device 123 includes a CCD, a CMOS (Complementary Metal Oxide Semiconductor), and the like, and is mounted on the image pickup device unit 124. Electric power is supplied to the image sensor 123 via the image sensor unit 124, and an electric signal is transmitted and controlled. In addition, an electrical signal is sent from the image sensor 123 to an image processing unit (not shown) via the image sensor unit 124.

  Here, the sensitivity characteristic of the image sensor 123 has a gentle mountain-shaped curve in the wavelength range of 300 nm to 800 nm. For this reason, even when an infrared ray having a wavelength of 750 nm or more is incident on the image sensor 123, charges are accumulated and reflected in the captured image. When infrared rays are incident on the image sensor 123 in this manner, the quality of the captured image is deteriorated.

  Therefore, when imaging a general subject, the optical filter 121 made of a glass plate material or the like having a function of transmitting visible light having a wavelength of 420 nm to 630 nm and shielding infrared light having a wavelength of 750 nm to 1100 nm is used as the imaging element 123. The light incident surface is aligned with the optical axis.

  Further, at least a part of the optical filter 121 is bonded to the image sensor 123 by an adhesive member 122. The adhesive member 122 has a discontinuous frame shape formed so as to surround the outer edge portion of the optical filter 121. Here, as the adhesive member 122, an acrylic resin adhesive having acrylic acid and a derivative as a main component, an acrylic resin adhesive tape having an acrylic adhesive applied to a base material, or the like can be used. In the first embodiment, a double-sided tape in which an acrylic pressure-sensitive adhesive is applied to both sides of a PET (Polyethylene Terephthalate) base material is used.

  Further, the imaging unit 120 is fastened and fixed to the master flange 112 by a plurality of metal screws 125.

  FIG. 2 is a front view on the light incident surface side of imaging unit 120 in the first embodiment. FIG. 3 is a schematic cross-sectional view taken along the line A-A ′ of the imaging unit 120 in FIG. 2. As shown in FIG. 2, the light incident surface of the image sensor 123 is covered with an optical filter 121 having an outer shape substantially the same as the outer shape of the image sensor 123. At least a part of the image sensor 123 and the optical filter 121 is bonded by an adhesive member 122.

  As illustrated in FIG. 3, an adhesive member 122 is interposed between the image sensor 123 and the optical filter 121 disposed to face the image sensor 123, and the image sensor 123 and the optical filter 121 are bonded to each other. A gap 130 is formed in part between the image sensor 123 and the optical filter 121.

  Here, steps for manufacturing the lens barrel 100 using the above-described components will be described. First, in step 1, the image sensor 123 is mounted on the image sensor unit 124. Next, in step 2, the adhesive member 122 is attached to the outer edge of the optical filter 121 and then pasted. Subsequently, in step 3, after aligning the optical filter 121 so as to cover the light incident surface of the image sensor 123, a predetermined load is applied and the image sensor 120 is completed by being attached to the image sensor 123. Finally, in step 4, the imaging unit 120 is fastened to the lens unit 110 with the screw 125, and the lens barrel 100 is completed.

  As described above, the first embodiment includes the image sensor 123 that converts incident light into an electrical signal, and the optical filter 121 that transmits visible light and shields infrared light. The optical filter 121 is an incident surface of the image sensor. Are arranged opposite to each other. Further, at least a part of the optical filter 121 is bonded to the image sensor 123 by the bonding member 122 and a gap 130 is formed. Therefore, even if a gas containing an organic component is generated from the adhesive member 122, the gas is ventilated to the outside of the image sensor 123 and the optical filter 121 through the gap 130. Therefore, the lens barrel 100 can be thinned while ensuring the image quality picked up by the image pickup device 123 without attaching an organic component to the light incident surface of the image pickup device 123 or the optical filter 121.

(Embodiment 2)
In the second embodiment, the same configurations as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  FIG. 4 is an exploded perspective view of the lens barrel 100 according to the second embodiment. As shown in FIG. 4, the lens barrel 100 includes a lens unit 110 and an imaging unit 140. Here, since the lens unit 110 is the same as that of the first embodiment, a description thereof will be omitted, and a characteristic part of the imaging unit 140 will be described in detail.

  As illustrated in FIG. 4, the imaging unit 140 includes a light shielding member 142 between the optical filter 121 and the imaging element 123. The light blocking member 142 is used to block unnecessary light from entering from the periphery of the image sensor 123 and has an opening 144 smaller than the light incident surface of the image sensor 123. The light shielding member 142 is made of a black PET (Polyethylene Terephthalate) film, a film coated with a black pigment, or the like that has been sandblasted on both sides in order to absorb unnecessary incident light or reflected light in the lens barrel 100. .

  At least a part of the surface of the light shielding member 142 facing the image sensor 123 is bonded to the image sensor 123 by the first adhesive member 143. At least a part of the surface of the light shielding member 142 facing the optical filter 121 is bonded to the optical filter 121 by the second adhesive member 141.

  The first adhesive member 143 has a frame shape that is continuously formed so as to surround the imaging element 123. The second adhesive member 141 has a discontinuous frame shape formed so as to surround the optical filter 121. As the first adhesive member and the second adhesive member, an acrylic resin-based adhesive, an acrylic resin-based adhesive tape, or the like can be used. In Embodiment 2, an acrylic adhesive is applied to both surfaces of the nonwoven fabric substrate. A double-sided tape coated with was used.

  FIG. 5 is a front view of the light incident surface side of the imaging unit 140 according to the second embodiment. FIG. 6 is a schematic cross-sectional view taken along line A-A ′ of the imaging unit 140 in FIG. 5. As shown in FIG. 5, the light incident surface of the image sensor 123 is covered with an optical filter 121 having substantially the same outer shape as the image sensor 123. The light shielding member 142 has almost the same outer shape as the optical filter.

  As shown in FIG. 6, the image sensor 123 and the light shielding member 142 are bonded by a first bonding member 143. Since the first adhesive member 143 is continuously formed so as to surround the imaging element 123, the outer peripheral portion of the imaging element 123 and the light shielding member 142 is sealed by the first adhesive member 143. At least a part of the optical filter 121 and the light shielding member 142 disposed to face the imaging element 123 are bonded by the second adhesive member 141. A gap 150 is formed in part between the optical filter 121 and the light shielding member 142.

  Here, steps for manufacturing the lens barrel 100 using the above-described components will be described. First, in step 1, the image sensor 123 is mounted on the image sensor unit 124. Next, in step 2, the second adhesive member is aligned with the outer edge of the optical filter 121 and then pasted. Next, in step 3, after aligning the light shielding member 142 and the optical filter 121, a predetermined load is applied and pasted. Next, in step 4, the first adhesive member 143 is pasted after being aligned with the outer edge portion of the light shielding member 142. Next, in step 5, the light shielding member 142 is aligned at a predetermined position, and then a predetermined load is applied and affixed to the image sensor 123 to complete the imaging unit 140. Finally, in step 6, the imaging unit 140 is fastened to the lens unit 110 with the screw 125, and the lens barrel 100 is completed.

  As described above, the second embodiment includes the light shielding member 142 between the image sensor 123 and the optical filter 121, and at least a part of the surface of the light shielding member 142 facing the image sensor 123 is the first adhesive member 143. As a result, the light-shielding member 142 is bonded to the optical filter 121 by the second adhesive member 141. Therefore, even if a gas containing an organic component is generated from the first adhesive member 143 and the second adhesive member 141, the gas is vented to the outside through the gap 150.

  Therefore, even if the light shielding member 151 for further improving the image quality is provided, the lens barrel 100 can be thinned.

(Embodiment 3)
In the third embodiment, the same configurations as those in the second embodiment are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  FIG. 7 is an exploded perspective view of the lens barrel 100 in the third embodiment. FIG. 8 is an enlarged exploded perspective view of the imaging unit 160 in the third embodiment. As shown in FIG. 7, the lens barrel 100 includes a lens unit 110 and an imaging unit 160. Here, since the lens unit 110 is the same as that of the first embodiment, a description thereof will be omitted, and a characteristic part of the imaging unit 160 will be described in detail. As illustrated in FIG. 8, the imaging unit 160 includes a light shielding member 151 having a larger outer shape than the optical filter 121 and the imaging element 123. The imaging unit 160 is fastened and fixed to the master flange 112 by a plurality of screws 125.

  FIG. 9 is a front view on the light incident surface side of imaging unit 160 in the third embodiment. FIG. 10 is a schematic cross-sectional view taken along the line A-A ′ of the imaging unit 160 in FIG. 9. The optical filter 121 is covered with an outer shape substantially the same as the outer shape of the image sensor 123.

  Here, the steps for manufacturing the lens barrel 100 using the above-described components are the same as those in the second embodiment, and thus description thereof is omitted.

  As described above, the third embodiment has the light shielding member 151 whose outer shape is larger than the outer shape of the optical filter 121.

  Therefore, when sticking shift occurs in the optical filter 121 or the like, the extending portion 152 can be held by a jig or the like, and the light shielding member 151 can be easily peeled off. Therefore, the optical filter 121 and the image sensor 123 can be easily separated and repaired.

  Furthermore, the extension part 152 of the light shielding member 151 is brought into contact with the master flange 112, and the gap between the lens part 110 and the imaging part 160 is closed. Therefore, it is possible to suppress flux and solder waste generated during soldering of a chip component or the like mounted on the imaging unit 160 from entering the lens unit 110, and it is possible to prevent degradation of the captured image.

(Other embodiments)
As Embodiments of the present invention, Embodiments 1 to 3 are exemplified. However, the present invention is not limited to this. Therefore, another embodiment of the present invention will be described. In addition, this invention is not restricted to these, It is applicable also to embodiment modified suitably.

  In Embodiment 2, an example in which the imaging element, the light shielding member, and the optical filter are bonded by the first adhesive member and the second adhesive member is illustrated, but the present invention is not limited to this.

  By making the area of the first adhesive member larger than the area of the second adhesive member, the adhesive strength between the imaging element and the light shielding member can be made higher than the adhesive strength between the light shielding member and the optical filter. In this way, when the optical filter is misaligned, only the optical filter can be peeled off, so that the imaging unit can be easily repaired. The same effect can be obtained by using an adhesive having a stronger adhesive force than the second adhesive member for the first adhesive member.

  In Embodiment 3, an example in which the imaging element and the light shielding member having an outer shape larger than that of the optical filter are bonded by the first adhesive member and the second adhesive member is illustrated, but the present invention is not limited thereto. I can't.

  By making the area of the first adhesive member smaller than the area of the second adhesive member, the adhesive strength between the imaging element and the light shielding member can be made lower than the adhesive strength between the light shielding member and the optical filter. By doing so, the optical filter and the light shielding member can be peeled off when the optical filter or the light shielding member is stuck, so that the imaging unit can be easily repaired. The same effect can also be obtained by using an adhesive having a weaker adhesive strength than the second adhesive member for the first adhesive member.

  According to the lens barrel of the present invention, it is possible to reduce the thickness of the lens barrel while ensuring the quality of an image picked up by the image sensor by bonding and fixing at least a part of the optical filter and the image sensor. This is useful for digital still cameras.

DESCRIPTION OF SYMBOLS 100 Lens barrel 110 Lens part 111 Lens fixing frame 112 Master flange 113 DC motor 120,140,160 Image pick-up part 121 Optical filter 122 Adhesive member 123 Image pick-up element 124 Image pick-up element unit 125 Screw 130,150 Space | gap 141 Second adhesive member 142 , 151 Light shielding member 143 First adhesive member 144 Opening portion 152 Extension portion

Claims (5)

A lens portion having a plurality of lenses;
An imaging unit having an imaging element;
Multiple screws,
With
The lens part is
A lens frame holding the lens;
A lens fixing frame that retracts and stores the lens frame body at the time of non-imaging;
A master flange fixed to the lens fixing frame;
With
The imaging unit
An image sensor that converts incident light into an electrical signal;
An image sensor unit that mounts the image sensor and transmits an electrical signal from the image sensor;
An optical filter disposed opposite to the incident surface of the image sensor;
A light shielding member disposed between the image sensor and the optical filter;
With
At least a part of a surface of the light shielding member facing the image sensor is bonded to the image sensor by a first adhesive member having an outer shape substantially the same as the image sensor,
At least a part of the surface of the light shielding member facing the optical filter is bonded to the optical filter by a second adhesive member whose outer shape is substantially the same as the optical filter,
Outer shape of the light shielding member is larger than the outer shape of the optical filter, the light blocking member portion extends is formed,
The imaging unit and the lens unit are fixed by fastening the imaging unit to the master flange with the plurality of screws,
When the lens unit and the imaging unit are fixed, the extending portion of the light shielding member, so as to close the gap of the imaging unit and the lens unit, is brought into contact with the master flange of the lens portion,
Lens barrel. Either one of the adhesive strength between the light shielding member and the imaging element by the first adhesive member and the adhesive strength between the light shielding member and the optical filter by the second adhesive member is higher than the other.
The lens barrel according to claim 1. The first adhesive member and the second adhesive member have a frame shape formed so as to surround an outer edge portion of the optical filter, and are discontinuous in a part of the frame shape of the second adhesive member. A gap is formed between the light shielding member and the optical filter by forming a section,
The adhesive strength between the light shielding member and the imaging element by the first adhesive member is higher than the adhesive strength between the light shielding member and the optical filter by the second adhesive member,
The lens barrel according to claim 2. The light shielding member has been subjected to antireflection treatment at least in part.
The lens barrel according to any one of claims 1 to 3 . The light shielding member may have a small opening than the light incident surface of the imaging element, is smaller outer shape than the image sensor unit,
The lens barrel according to any one of claims 1 to 4 .

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