JP4999508B2 - Lens unit - Google Patents

Description

  The present invention relates to a lens unit used in a camera.

Due to the high performance and low cost of imaging elements and lenses that constitute a part of the camera, the use of the camera has expanded, and the camera has been incorporated into, for example, an outdoor monitoring device or an in-vehicle camera device.
As this outdoor monitoring device, for example, it is a system that records and monitors the movement of people and cars in parks, roads, etc., and due to the increased awareness of crime prevention, many outdoor monitoring devices have been installed in the city. It is coming.
The in-vehicle camera device is, for example, a system in which an in-vehicle camera is attached to the side of the passenger seat, which is a blind spot from the driver's seat, behind the vehicle seat, and the like, and can be confirmed on a monitor screen in the vehicle. There is also an in-vehicle camera device that has an image recognition function and is used for purposes other than visual assistance. That is, the system detects the white line of the road with an in-vehicle camera, accurately determines the position of the car, and prevents a collision accident. As described above, a plurality of in-vehicle cameras are provided for each vehicle.

Since the lens unit of a camera mounted on such a system may be installed in an environment where the lens surface is exposed to rain and wind, heat resistance and moisture resistance are required. In order to meet such demands, various structures have been proposed in the past (see, for example, Patent Document 1).
Patent Document 1 discloses a camera in which the surface of a lens or a protective plate that is in contact with the outside is not condensed even when the CCD or a mounting board on which the CCD is mounted generates heat and the internal temperature rises. . Specifically, four lenses are arranged along the optical axis direction by a lens barrel, an O-ring is disposed between the first lens and the lens barrel, and the space between the fourth lens and the lens barrel. An O-ring is placed on the second lens, a space between the first lens and the second lens, a space between the second lens and the third lens, and a third lens and a fourth lens. A configuration is disclosed in which a space is formed between the two spaces so that air does not move between these spaces.

JP 2005-266276 A

  Here, for such a camera, there is a demand for improving the quality of the sealing performance. Conventionally, various configurations have been proposed to meet the demand. In addition, there is a demand for suppressing variation in quality for each product, and various configurations have been proposed in the past to meet this demand.

  An object of the present invention is to provide a lens unit capable of ensuring a higher level of quality than the conventional case.

For this purpose, a lens unit to which the present invention is applied is a lens unit used in a camera module in which a gap between the outer peripheral surface of the lens unit and an outer case covering the lens unit is sealed with a seal member . includes a plurality of lenses for forming an image, a receiving portion for receiving a tubular formed on Rutotomoni the plurality of lenses of openings at both ends, and, most other end of the plurality of lenses to be inserted from one end A holder in which a reduced diameter portion that engages with a peripheral edge portion other than the optical path in the other end side lens located at the other end, the one end side lens located on the most end side among the plurality of lenses, and the holder one end sealing section for sealing positioned between, and the other end side seal portion for sealing located at the other side of the holder than the one sealing section, the holder Definitive wherein formed between the end sealing section sealing position by the seal position of the other end seal unit includes a communicating passage communicating with each other externally and the receiving portion of the holder, and the other end The seal portion includes an optical filter attached to the reduced diameter portion of the holder from the other end side, an attachment portion formed on the reduced diameter portion of the holder in a concave shape corresponding to the outer shape of the optical filter, and the attachment A groove portion extending along an inner peripheral edge of the reduced diameter portion at the concave portion of the portion, and being positioned in the concave portion of the attachment portion and entering the groove portion, and the optical filter and the attachment portion. sealing between, and is configured with an adhesive for bonding the optical filter to the reduced diameter portion, by said communication passage, sheet by the seal member for sealing between said outer case Provided from Le positioned on the image side, the sealing member for sealing between the said outer casing is characterized in that provided on the image side of the object side lens surface of the one end side lens.

Here, the mounting portion, the Rukoto which have a distance defining portion for defining the distance to the other end side lens of the optical filter to be attached to the attachment portion by the adhesive can be characterized. Also, the attachment portion may be characterized that you have a surface of the said optical filter when attaching the optical filter to the mounting portion is formed to fit the position of the surface of the reduced diameter portion other than the mounting portion Can do. Also, the adhesive can be characterized in that the ultraviolet curable resin. The optical filter may be an infrared filter.

In addition , it may further include a closing member that closes the communication path of the holder. The closing member may be made of an ultraviolet curable resin.

  Here, the holder may have a through hole extending in a direction different from the direction of the optical axis between the one end and the other end in the direction of the optical axis.

  According to the present invention, it is possible to provide a lens unit capable of ensuring a higher level of quality than in the conventional case.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
[First Embodiment]
FIG. 1 is a schematic configuration diagram showing a lens unit 1 according to the first embodiment.
A lens unit 1 shown in FIG. 1 is for forming an image of an object on the image side, and is, for example, a wide-angle lens used in an in-vehicle camera. The lens unit 1 includes a lens barrel (holder, barrel) 2 that forms a main body of the lens unit 1, a lens group 3 that is held by the lens barrel 2 to form an optical system, and a filter that transmits light from the lens group 3. (Optical filter) 6. The filter 6 is obtained by depositing a multilayer film on glass for the purpose of removing a specific frequency component of external light. In this embodiment, an infrared filter (IRCF: Infrared Cut Filter) is used. .

  The lens unit 1 has a predetermined aperture, a diaphragm member 11 disposed in the lens group 3, and a seal member (one end side seal portion, which is interposed between the lens barrel 2 and the lens group 3). First seal portion) 4. The diaphragm member 11 is a disk-shaped light shielding sheet, and is fixed by upper and lower lenses to limit the range of the passing light. The main material of the diaphragm member 11 is a plastic material such as PET (stretched polyester) and carbon black.

FIG. 2 is an exploded view of the lens unit 1.
As shown in FIG. 2, the lens barrel 2 is a cylindrical member having openings at both ends. That is, the lens barrel 2 has an opening 21 at the end (one end) on the object side (outside, incident side), and the opening 22 at the end (other end) on the image side (inside, emission side). Have Further, an end portion on the image side of the lens barrel 2 has a reduced diameter portion 23 formed so as to narrow the opening 22. The end face 23a of the reduced diameter portion 23 is formed in a shape that fulfills the aperture function. The opening 22 is narrower than the opening 21.

An attachment portion 23 b for attaching the filter 6 to the lens barrel 2 is formed on the image side surface of the reduced diameter portion 23. In addition, a groove 23c extending along the inner peripheral edge of the reduced diameter portion 23 is formed in the attachment portion 23b.
More specifically, the attachment portion 23b has a concave shape corresponding to the outer shape of the filter 6. When the filter 6 is attached, the surface of the filter 6 (image side surface) is the position of the image side surface of the reduced diameter portion 23. It is formed to fit.
Moreover, the attachment part 23b has the distance regulation part 23d (refer FIG. 1) which prescribes | regulates the distance with respect to the lens 34 of the filter 6 attached to the attachment part 23b with an adhesive agent.

  If it demonstrates further, attachment of the filter 6 is performed by the adhesive agent (other end side seal part, 2nd seal part) 5 (refer FIG. 1). That is, the adhesive 5 is applied between the attachment portion 23b of the reduced diameter portion 23 and the back surface (object side surface) 6a of the filter (the other end side seal portion, the second seal portion) 6 so that the filter 6 is fixed to the lens barrel 2. A part (excess part) of the adhesive 5 enters the groove part 23c of the attachment part 23b. For this reason, it is prevented that the adhesive 5 protrudes from the reduced diameter portion 23 and blocks the optical path. Further, the adhesive 5 seals between the attachment portion 23b of the reduced diameter portion 23 and the back surface 6a of the filter 6, and airtightness is ensured. That is, the adhesive 5 has the same sealing function as the seal member 4. For this reason, one seal member can be omitted, and the number of components of the lens unit 1 can be reduced. Note that it is conceivable to use a thermosetting resin or an ultraviolet curable resin as the material of the adhesive 5.

The lens barrel 2 has a receiving portion 24 defined by the inner peripheral surface 2a. The receiving portion 24 is for forming a space for receiving the lens group 3, and is formed in a plurality of steps so that the lens group 3 can be positioned and held. More specifically, the receiving portion 24 is configured by a circular inner peripheral surface, and has a circular portion 24 a that receives the lens 31. In addition, the receiving portion 24 is configured by an inner peripheral surface of a polygonal shape having eight or more corners, and is configured by a polygonal shape portion 24b that receives the lens 32 and an inner peripheral surface of a polygonal shape having eight or more corners, and receives the lens 33. (A part of a holder that accommodates another lens) 24 c and a polygonal portion 24 d that is configured by a polygonal inner peripheral surface of eight or more corners and receives the lens 34.
When the lens group 3 is inserted into the receiving portion 24 of the lens barrel 2 and attached, desired optical characteristics can be obtained. The lens barrel 2 is made of a mixture of polycarbonate resin, glass fiber, and black pigment such as carbon black.

  The lens barrel 2 has a male screw 26 screwed to the outer peripheral surface 2b at the end on the image side. The male screw 26 is used to attach to a mount 202 (see FIG. 4) described later. The lens barrel 2 is formed to protrude from the outer peripheral surface 2b of the end portion on the object side, and is formed in a concave shape on the flange portion 27 for positioning with the case member, and is attached to the case member. And a turning portion 28 that can be engaged with a tool (not shown).

  The lens group 3 includes a plurality of lenses. That is, the lens group 3 includes a lens (one end side lens, first lens) 31, a lens 32, a lens 33, and a lens (other end side lens, second lens) 34. These lens 31, lens 32, lens 33, and lens 34 are arranged in order from the object side. That is, the lens 31 is an object side lens closest to the object side, and the lens 34 is an image side lens closest to the image side. The lens 32 and the lens 33 are intermediate lenses positioned between the lens 31 and the lens 34.

  The lens 31 is made of glass and is therefore resistant to scratches and heat. The lens 31 has a recess 31 a formed on the peripheral edge on the side close to the adjacent lens 32. The recess 31a is for forming a space in which the incident side seal member 4 is disposed. In other words, a heat caulking portion K (see FIG. 1) for locking the outer peripheral portion of the lens 31 is formed on the opening 21 side of the lens barrel 2. The lenses 31, 32, 33, 34 and the diaphragm members 11, 12 are fixed to the receiving portion 24 of the lens barrel 2 by the heat crimping portion K.

  The lenses 32, 33, and 34 are plastic lenses made of an amorphous polyolefin resin, a polycarbonate resin, or an acrylic resin and manufactured by injection molding. The lenses 32, 33, and 34 have a circular outer periphery, and gate trace portions 32 b, 33 b, and 34 b formed on the outer peripheral surface when injection molded are left on a part of the outer peripheral surface.

  The seal member 4 is an O-ring member, and examples of the material thereof include NBR (nitrile rubber), EPDM (ethylene pyropyrene rubber), FKM (fluorine rubber), CR (chloroprene rubber), and VMQ (silicone rubber). , UR (polyurethane rubber), NR (natural rubber), or ACM (acrylic rubber) may be used.

More specifically, the seal member 4 is engaged with the receiving portion 24 of the lens barrel 2 and the lens 31 to eliminate a gap between them. As described above, the airtight state of the receiving portion 24 with respect to the outside on the object side is formed by the seal member 4. On the other hand, the airtight state of the receiving portion 24 with respect to the outside on the image side is formed by the adhesive 5 for attaching the filter 6 to the reduced diameter portion 23 as described above.
That is, the region sandwiched between the seal member 4 and the adhesive 5 in the receiving portion 24 is airtight with the outside on the object side and the outside on the image side. More specifically, the lens chamber L, which is a space defined by the lens 31, the inner peripheral surface 2a of the lens barrel 2, the seal member 4, the filter 6, and the adhesive 5, is established in an airtight state from the outside. The Thereby, it is possible to more reliably prevent condensation on the inner surface of the lens group 3, particularly the inner surface of the lens 31 (surface close to the lens 32). Further, by increasing the volume of the lens chamber L, it is possible to provide a heat insulating effect, and to suppress the influence of external temperature changes on the inside of the apparatus.

FIG. 3 is a diagram illustrating an inspection apparatus 100 that inspects the airtight state of the lens unit 1.
The inspection apparatus 100 shown in FIG. 3 has a receiving base 101 for receiving the lens unit 1, an attachment member 102 for attaching the lens unit 1 to the receiving base 101, and nitrogen (N ₂ ) or dry air is applied to the receiving base 101. A pipe 103 for supplying at a pressure of In addition, the inspection apparatus 100 includes a pressure gauge 104 and a leak inspection device (leak detector) 105 disposed in the middle of the pipe 103.

  The cradle 101 includes a receiving portion 101a formed so as to receive the lens unit 1, a connecting portion 101b for connecting the receiving portion 101a and the pipe 103 to each other, and a female screw portion 101c. The attachment member 102 has a male screw portion 102c formed so as to be capable of screwing with the female screw portion 101c of the cradle 101.

  The pressure gauge 104 is a device for displaying the pressure of air or the like supplied to the receiving portion 101 a of the receiving base 101 through the pipe 103. The leak tester 105 is a device for detecting leakage of air supplied to the receiving portion 101a at a predetermined pressure, that is, a gas flow.

The inspection method performed using the inspection apparatus 100 is performed as follows. First, the lens unit 1 is inserted into the receiving portion 101a of the receiving base 101 with the seal member 106 interposed therebetween. The lens unit 1 is not yet attached with the filter 6 with the adhesive 5.
After the filter unit 6 is not attached to the lens unit 1 in the receiving portion 101 a, the attachment member 102 is screwed to the receiving base 101. Accordingly, the flange portion 27 of the lens unit 1 is fixed by the interaction between the cradle 101 and the mounting member 102.

  When the lens unit 1 is fixed in this manner, a space A is defined by the receiving portion 101a, the seal member 106, and the outer peripheral surface 2b of the lens unit 1. The space A communicates with the lens chamber L of the lens unit 1 through the opening 22. For this reason, air or the like supplied at a predetermined pressure through the pipe 103 is sent to the lens chamber L of the receiving unit 24 through the connection unit 101 b, the space A, and the opening 22. When the lens chamber L is not airtight due to a poor attachment of the seal member 4 or the like, air leaks and can be detected by the leak tester 105.

In this way, the lens unit 1 is attached to the inspection apparatus 100, and air or the like is pressurized with a predetermined pressure. At that time, the presence or absence of sealing failure in the lens chamber L is confirmed by detecting leakage of air or the like. be able to. If there is no sealing failure of the lens chamber L, the lens unit 1 is removed from the inspection apparatus 100 and the filter 6 is attached to the reduced diameter portion 23 of the lens unit 1 with the adhesive 5. Thereby, the lens chamber L in the lens unit 1 that has been subjected to the airtightness inspection can be sealed. The airtight state can be confirmed by the adhesive 5 by visually recognizing the appearance of the lens unit 1.
By performing such an airtight inspection on all the products of the lens unit 1 before shipment in a stage before being incorporated into the camera, it is possible to detect defective products and provide high-quality products. .
In addition, although the test | inspection apparatus 100 employ | adopts the form to pressurize, it can also consider employ | adopting the form to reduce pressure. In this embodiment, the cradle 101 and the mounting member 102 are fitted by screw fitting of the male screw portion 102c and the female screw portion 101c. However, the mounting member 102 is fixed to the cradle 101 with a constant force. It may be pressed against.

FIG. 4 is a schematic configuration diagram showing the configuration of the camera module 200.
A camera module 200 shown in FIG. 4 includes the lens unit 1 to which the filter 6 is attached. That is, the camera module 200 includes an upper case (camera case) 201 that is an exterior component, and a mount (flange, pedestal) 202 that holds the lens unit 1. The camera module 200 also includes a seal member 203 and a package sensor (imaging device) 204.

  The upper case 201 is a member that exposes the end of the lens unit 1 on the opening 21 side and covers other parts. The mount 202 is disposed inside the upper case 201 and has a female screw 202 a that is screwed into the male screw 26 of the lens unit 1. The seal member 203 is a member interposed between the inner surface of the upper case 201 and the outer peripheral surface 2 b of the lens unit 1, and is a member for maintaining the airtightness inside the upper case 201.

  The package sensor 204 is disposed inside the upper case 201 and is disposed at a position for receiving an image of an object formed by the lens unit 1. The package sensor 204 includes a CCD (Charge Coupled Device), a CMOS (Complementary Metal-Oxide Semiconductor), and the like, and converts the light that is collected through the lens unit 1 and arrives into an electrical signal. The converted electric signal is converted into analog data or digital data which is a component of image data photographed by the camera.

[Second Embodiment]
FIG. 5 is a schematic configuration diagram showing a lens unit 1 ′ according to the second embodiment. Since the basic configuration of the lens unit 1 ′ is the same as that of the lens unit 1, the same reference numerals are used for common parts and members, and the description thereof may be omitted.
The lens barrel 2 of the lens unit 1 ′ shown in FIG. 5 has a through hole (a communication path, a hole for confirming an airtight state) 25 ′ formed through the wall of the lens barrel 2. This through hole 25 ′ extends in a direction different from the direction of the optical axis. In addition, the through hole 25 ′ passes through the inner peripheral surface 2 a side and the outer peripheral surface 2 b side, and thereby allows the receiving portion 24 and the outside of the lens barrel 2 to communicate with each other. That is, the receiving portion 24 communicates with the outside of the lens barrel 2 through the through hole 25 ′ without using the openings 21 and 22.

  More specifically, as shown in FIG. 5, the blocking member 7 ′ is inserted into the through hole 25 ′. As the material of the closing member 7 ′, it is conceivable to use a rubber material, an adhesive, or an ultraviolet curable resin. By using the ultraviolet curable resin, the work of closing the through hole 25 ′ can be easily and reliably performed.

The through hole 25 ′ is located in the middle of the seal member 4, the adhesive 5, and the filter 6 with respect to the direction of the optical axis in the lens barrel 2. In other words, a through hole 25 ′ is formed at a position sandwiched between the seal member 4 and the adhesive 5. Further, since the through hole 25 ′ is located on the image side with respect to the seal member 203 with the camera case, the through hole 25 ′ is not exposed to the outside without providing a member that hides the through hole 25 ′. Further, since it is sealed by the sealing member 203 and the camera case to be extrapolated, it is not directly exposed to wind and rain.
If the position of the seal member 203 is fixed using the flange portion 27 as in this embodiment, it is not necessary to separately provide positioning means for the seal member 203 in the lens barrel 2.

6 is a cross-sectional view of FIG. 5 showing the positional relationship between the lens barrel 2 and the lens 33. Since the positional relationship between the lens barrel 2 and the lenses 32, 33, and 34 is the same, as a representative example, the positional relationship between the lens barrel 2 and the lens 33 is shown in FIG.
As shown in FIG. 6, the inner peripheral surface of the polygonal portion 24 c of the lens barrel 2 and the circular outer peripheral surface 33 c of the lens 33 are in pressure contact at the press contact portions P and Pa. In this way, the lens 33 is held by the lens barrel 2 by pressing the outer peripheral surface 33c of the lens 33 against the inner peripheral surface of the polygonal portion 24c.

  Further, the gate trace portion 33 b formed on a part of the outer peripheral surface 33 c of the lens 33 is located closer to the center of the lens 33 than the outer peripheral surface 33 c of the lens 33. For this reason, the gate trace part 33b is not pressed against the polygonal part 24c.

  More specifically, of the plurality of pressure contact portions P, the pressure contact portions Pa located on both sides of the gate trace portion 33b are in the vicinity of the gate trace portion 33b with the reference line B connecting the center position C and the optical axis in the gate trace portion 33b as the center. And it is located on both the left and right sides. Further, the gap (notch portion) G in the gate trace portion 33b is larger than the maximum separation distance between the outer peripheral surface 33c of the lens 33 and the inner peripheral surface of the polygonal portion 24c. For this reason, it is possible to prevent the optical axis from being biased toward the gate trace portion 33b due to a decrease in roundness due to expansion and contraction due to a change in temperature and humidity.

  Further, the lens 33 is arranged so that the gate trace portion 33b faces the through hole 25 ′. In other words, the gap G of the lens 33 is close to the through hole 25 ′. For this reason, even when a large amount of the blocking member 7 ′ is injected into the through hole 25 ′ when the through hole 25 ′ is sealed with the blocking member 7 ′ after the airtightness test described later, the blocking member 7 ′ enters the lens chamber L. It is reduced that it enters and adversely affects the optical path.

FIG. 7 is a diagram illustrating an inspection apparatus 300 that inspects the airtight state of the lens unit 1 ′. In addition, since the basic configuration of the inspection apparatus 300 is the same as that of the inspection apparatus 100, the same reference numerals are used for common parts and members, and the description thereof may be omitted.
An inspection apparatus 300 illustrated in FIG. 7 includes a cradle 301 corresponding to the cradle 101 of the inspection apparatus 100. The cradle 301 includes a receiving part 301a formed so as to receive the lens unit 1 ′, a connecting part 301b, and a female screw part 301c. The receiving portion 301a, the connecting portion 301b, and the female screw portion 301c correspond to the receiving portion 101a, the connecting portion 101b, and the female screw portion 101c of the inspection apparatus 100. More specifically, the connecting portion 301b extends in the lateral direction from the receiving portion 301a and connects the receiving portion 301a and the pipe 103 to each other.
The inspection apparatus 300 includes not only the seal member 106 interposed between the cradle 301 and the lens unit 1 ′ but also a seal member 307.

  The inspection method performed using the inspection apparatus 300 is performed as follows. First, the lens unit 1 ′ is inserted into the receiving portion 301 a of the receiving base 301 through the seal members 106 and 307, and then the attachment member 102 is screwed to the receiving base 301. Thereby, the flange portion 27 of the lens unit 1 ′ is fixed by the interaction between the cradle 301 and the mounting member 102.

  When the lens unit 1 ′ is fixed in this manner, a space A is defined by the receiving portion 301a, the seal member 106, the seal member 307, and the outer peripheral surface 2b of the lens unit 1 ′. The space A communicates with the connection portion 301b of the cradle 301 and also communicates with the through hole 25 ′ of the lens unit 1 ′. For this reason, air or the like supplied at a predetermined pressure through the pipe 103 is sent to the through hole 25 ′ via the connection portion 301 b and the space A, and finally reaches the lens chamber L of the receiving portion 24. If the lens chamber L is not airtight, air leaks and can be detected by the leak tester 105.

  In this way, the lens unit 1 ′ is attached to the inspection apparatus 300, air or the like is pressurized with a predetermined pressure, and at that time, the presence or absence of sealing failure of the lens chamber L is confirmed by detecting leakage of air or the like. can do. If there is no defective sealing of the lens chamber L, the lens unit 1 ′ is removed from the inspection apparatus 300, the blocking member 7 ′ is inserted into the through hole 25 ′ of the lens unit 1 ′, and cured by irradiating with ultraviolet rays. Thereby, the lens chamber L in the lens unit 1 ′ that has been subjected to the airtightness inspection can be sealed. By performing such an airtight inspection on all the products of the lens unit 1 ′ before shipment, defective products can be detected, and high-quality products can be provided.

[Third Embodiment]
FIG. 8 is a schematic configuration diagram showing a lens unit 8 according to the third embodiment. Since the lens unit 8 has the same basic configuration as the lens unit 1 according to the first embodiment, the same reference numerals are used for common parts and members, and the description thereof may be omitted.
The lens unit 8 shown in FIG. 8 does not include the filter 6 (see FIG. 1) included in the lens unit 1. Therefore, the lens unit 8 is not provided with the mounting portion 23b (see FIG. 2) and the groove portion 23c (see FIG. 2) in the lens barrel 2.

The lens unit 8 also has an adhesive 5 for sealing between the end surface (outside of the reduced diameter portion) 23 a of the lens barrel 2 and the lens 34. That is, the lens chamber L in the present embodiment is defined by the lens 31, the inner peripheral surface 2 a of the lens barrel 2, the seal member 4, the inner surface of the reduced diameter portion 23, and the adhesive 5.
The inspection of the airtight state of the lens unit 8 is the same as in the case of the first embodiment.

[Fourth Embodiment]
FIG. 9 is a schematic configuration diagram showing a lens unit 8 ′ according to the fourth embodiment. The lens unit 8 ′ has the same basic configuration as the lens unit 1 ′ according to the second embodiment. Therefore, the same reference numerals are used for the common parts and members, and the description thereof may be omitted. .
The lens barrel 2 of the lens unit 8 ′ shown in FIG. 9 has the same through hole 25 ′ as the lens unit 1 ′ according to the second embodiment. Further, the blocking member 7 ′ is inserted into the through hole 25 ′ in the same manner as the lens unit 1 ′ according to the second embodiment.
A lens unit 8 ′ shown in FIG. 9 has an adhesive 5 for sealing between the end surface 23a of the lens barrel 2 and the lens 34, similarly to the lens unit 8 according to the third embodiment.

  According to the first to fourth embodiments described above, the lens group 3 is inserted into the receiving portion 24 from the object side of the lens barrel 2 and the object side is sealed by the seal member 4 while the image side is sealed. The adhesive 5 is applied to the lens barrel 2 from the image side of the lens barrel 2. For this reason, it is possible to separately perform the work of assembling the lens group 3 to the lens barrel 2 and the work of sealing the image side of the lens barrel 2. Further, sealing can be performed after the lens group 3 is assembled to the lens barrel 2. For this reason, the work content is simplified, and sealing can be performed more reliably.

  Further, by providing the through hole 25 ', it becomes possible to perform an airtight inspection on all the products of the lens unit 1 before shipment, thereby detecting a defective product and providing a high-quality product. It becomes possible.

It is a schematic block diagram which shows the lens unit which concerns on 1st Embodiment. It is an exploded view of a lens unit. It is a figure explaining the test | inspection apparatus which test | inspects the airtight state of a lens unit. It is a schematic block diagram which shows the structure of a camera module. It is a schematic block diagram which shows the lens unit which concerns on 2nd Embodiment. FIG. 6 is a cross-sectional view of FIG. 5 showing the positional relationship between the lens barrel and the lens. It is a figure explaining the test | inspection apparatus which test | inspects the airtight state of a lens unit. It is a schematic block diagram which shows the lens unit which concerns on 3rd Embodiment. It is a schematic block diagram which shows the lens unit which concerns on 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1 ', 8,8' ... Lens unit, 11, 12 ... Diaphragm member, 2 ... Lens barrel, 2a ... Inner peripheral surface, 2b ... Outer peripheral surface, 21,22 ... Opening part, 23 ... Reduced diameter part, 23a ... end face, 23b ... mounting part, 24 ... receiving part, 24a ... circular part, 24b, 24c, 24d ... polygonal part, 25 '... through hole, 26 ... male screw, 27 ... flange part, 28 ... turning part, 3 ... Lens group, 31, 32, 33, 34 ... Lens, 31a ... Recess, 32b, 33b, 34b ... Gate trace, 33c ... Outer peripheral surface, 4 ... Seal member, 5 ... Adhesive, 6 ... Filter, 7 '... Blocking Member, B ... reference line, C ... center position, G ... gap, K ... thermal crimping part, L ... lens chamber, P, Pa ... pressure contact part

Claims (7)

In a lens unit used in a camera module in which a gap between the outer peripheral surface of the lens unit and an outer case covering the lens unit is sealed with a seal member,
A plurality of lenses for forming an image of the object;
Has a receiving portion for receiving the opposite ends opening in the tubular formed on Rutotomoni the plurality of lenses, and, other than the optical path at the other end side lens positioned closest to the other end of the plurality of lenses to be inserted from one end A holder in which a reduced diameter portion engaged with the peripheral portion is formed at the other end;
One end side seal portion that seals between the one end side lens located on the most end side of the plurality of lenses and the holder; and
The other end-side seal portion that seals on the other end side of the holder from the one end-side seal portion; and
A communication path formed between a sealing position of the one end side sealing portion in the holder and a sealing position of the other end side sealing portion, and communicating the outside of the holder and the receiving portion with each other;
Including
The other end side seal portion is
An optical filter attached to the reduced diameter portion of the holder from the other end side;
A mounting portion formed in a concave shape corresponding to the outer shape of the optical filter in the reduced diameter portion of the holder;
A groove portion extending along an inner peripheral edge of the reduced diameter portion at the concave portion of the attachment portion;
An adhesive that is located in the concave portion of the attachment portion and enters the groove portion to seal between the optical filter and the attachment portion, and adheres the optical filter to the reduced diameter portion;
Composed of
The communication path is provided on the image side from a sealing position by the sealing member that seals between the outer case,
The lens unit , wherein the seal member that seals between the outer case is provided on the image side of the object side lens surface of the one end side lens .   2. The lens unit according to claim 1, wherein the attachment portion includes a distance defining portion that defines a distance of the optical filter attached to the attachment portion with the adhesive with respect to the lens on the other end side.   3. The mounting portion is formed such that when the optical filter is attached to the attachment portion, the surface of the optical filter is aligned with the position of the surface of the reduced diameter portion other than the attachment portion. The lens unit described in 1.   The lens unit according to claim 2, wherein the adhesive is an ultraviolet curable resin.   The lens unit according to claim 1, wherein the optical filter is an infrared filter. The lens unit according to any one of claims 1 to 5, further comprising a closure member for closing the communicating passage of the holder. The lens unit according to claim 6 , wherein a material of the blocking member is an ultraviolet curable resin.

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