JP2005266588A - Optical unit, optical unit manufacturing method, and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical unit which allows an optical element having an optical surface having a free curved surface shape to be surely positioned and built in with a simple structure even in the case that the optical element has a small shape. <P>SOLUTION: In an optical unit 10, two optical elements (a first optical element 11 and a second optical element 12) are integrally fixed with a support member 13 having an aperture part (a diaphragm hole 13a) formed therein, between them. The optical elements have light incidence surfaces (a first light incidence surface 11a and a second light incidence surface 12a), at least one of light reflecting surfaces (a first reflecting surface 11b and a second reflecting surface 11b, 11c) formed into a free curved surface shape, the other non-optical surfaces 11e, 11f, 12e, and 12f, and at least one of projecting pieces 11g, 11h, 12g, and 12h formed projectingly from non-optical surfaces. Projecting pieces 11g, 11h, 12g, and 12h are cut off after two optical elements are mutually fixed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical unit in which a plurality of optical elements having an optical surface having a free-form surface shape are integrated, a method for manufacturing the optical unit, and an imaging device incorporating the optical unit.

  Many imaging devices using a coaxial optical system have been filed as imaging devices incorporated in digital cameras, mobile phones with cameras, and the like. The coaxial system is an optical system in which optical elements such as lenses are provided in a rotationally symmetrical manner with respect to the optical axis of the optical system (the axis connecting the aperture of the imaging system and the center of the imaging screen). A coaxial imaging device is disclosed in, for example, Patent Documents 1 to 3 listed below.

  Digital cameras and camera-equipped mobile phones tend to be smaller, thinner and higher performance. Therefore, it is necessary to reduce the size, the thickness, and the performance of the imaging device applied to these imaging devices. In order to reduce the size and thickness of the imaging device, it is necessary to reduce the number of lenses when using a coaxial optical system. However, if the number of lenses is reduced, it becomes difficult to suppress distortion occurring in the optical system, and the image quality deteriorates. Conversely, in order to improve the image quality and improve the performance of the imaging apparatus, it is necessary to increase the number of lenses, and the imaging apparatus becomes larger in the optical axis direction. As described above, for an imaging apparatus using a coaxial optical system, there is an inverse relationship between downsizing and thinning and high performance, and it is difficult to achieve both.

  As one means for solving this problem, an imaging apparatus using a decentered optical system has been proposed. For example, Patent Documents 4 to 6 below describe image pickup apparatuses configured by an image pickup optical system to which a prism having an optical surface formed in a free-form surface is applied.

  The aim of the techniques described in these Patent Documents 4 to 6 is to form an imaging optical system using a prism and to use a free-form surface for the light incident surface, light exit surface, or reflecting surface of the prism. In other words, a compact and high-quality image can be obtained. In particular, in Patent Document 5 and Patent Document 6, two prisms are combined, and the second optical element closer to the light incident surface, reflecting surface, light exit surface, and imaging surface of the first optical element closer to the object. It is described that free-form surfaces are used for all seven surfaces including the light incident surface, the two reflecting surfaces, and the light emitting surface.

  The combination optical element described in Patent Document 7 has two optical elements (prisms). The optical element has three surfaces having an optical action and two opposite side surfaces. One of the surfaces having optical action is a curved surface, and is formed so as to be plane-symmetric (rotationally asymmetric) with respect to only one symmetry plane. The first optical element totally reflects light incident from the first surface on the second surface, reflects light reflected on the second surface on the third surface, and reflects light reflected on the third surface to the second surface. Inject through the surface. The second optical element transmits light incident from the fourth surface to a fifth surface formed in the same shape as the third surface of the first optical element.

  Protruding portions are provided as positioning portions on the two side surfaces of the first and second optical elements, respectively. The first and second optical elements are aligned and fixed using protrusions. A gap is provided between the third and fifth surfaces (curved surfaces) of the two optical elements (prisms) facing each other, and is filled with an adhesive.

Further, this optical element is applied to an observation system such as a telescope or binoculars, and superimposes the image information of the display means on the image information from the outside to the observer and displays it in the same field of view.
JP 2000-272587 A Japanese Patent Laid-Open No. 2002-267928 JP 2002-320122 A Japanese Patent Laid-Open No. 11-326766 JP 2002-196243 A JP 2003-84200 A JP-A-9-73005

  However, when an optical unit is configured by combining a plurality of decentered optical systems using prisms having free-form surfaces, as in the imaging devices described in Patent Documents 4 to 7, as described in Patent Documents 1 to 3 Alignment is difficult because it is not possible to use a cylindrical lens frame that is used when configuring an optical unit of a coaxial optical system. If a holding member having a complicated configuration is provided in order to combine the prisms with high accuracy, a space for accommodating the holding member in addition to the prism as the imaging device is newly required around the prism.

  Therefore, even if the volume occupied by the imaging optical system is reduced by adopting the decentration optical system, the volume occupied by the mechanism that holds the imaging optical system is required separately, thereby reducing the size and thickness of the entire imaging apparatus. The effect of conversion will fade. As the prism to be combined becomes smaller, higher dimensional accuracy in absolute dimensions is required, and a more advanced mechanism for the holding member that satisfies this requirement is required. In particular, the optical element described in Patent Document 7 is premised on application to an observation system arranged across the observer's field of view, and is not intended to be as small as possible. In other words, it does not take into account the handling of optical elements in assembly work when downsizing the optical system of an imaging device incorporated in an imaging device to be reduced in size or thickness, such as a digital camera or a mobile phone with a camera. .

  Therefore, the present invention provides an optical unit that can be reliably positioned and assembled with a simple structure even if the optical element having an optical surface having a free-form surface has a small shape, this optical unit manufacturing method, and this optical unit An object of the present invention is to provide an imaging device comprising:

  In the optical unit according to the present invention, two optical elements are fixed integrally with a support member having an opening formed therebetween. The optical element includes a light incident surface, a light reflecting surface, at least one light reflecting surface formed in a free-form surface, other non-optical surfaces, and at least one convex formed protruding from the non-optical surfaces. And have a piece. The convex piece is used when the two optical elements are relatively positioned, and is cut and removed after the two optical elements are fixed to each other.

  In the optical unit manufacturing method according to the present invention, in order to fix the two optical elements integrally with the support member having an opening through which the light beam passes, an adhesive material is provided between the optical element and the support member. The adhesive coating step to be applied, and the convex piece formed on the non-optical surface of one optical element are held, and the convex piece formed on the non-optical surface of the other optical element is sandwiched between A positioning step of urging the optical element toward the convex piece; and a cutting step of cutting the convex pieces of the two optical elements after the two optical elements are fixed to the support member.

  The imaging apparatus according to the present invention includes an optical unit according to the present invention and an object image formed by the imaging optical system in which a light receiving surface is disposed on the imaging surface of the imaging optical system including the optical unit. An image sensor that converts to an electrical signal, a processing unit that obtains image data by applying predetermined electrical processing to the electrical signal obtained from the image sensor, and image data from the processing unit is recorded on the applied information recording medium Recording means.

  According to the optical unit of the present invention, the two optical elements are relatively positioned using the convex pieces formed on the optical elements, and the convex pieces are cut and removed after the optical elements are fixed to the support member. Therefore, with a simple structure in which the convex piece is formed on the optical element, even if the optical element has a small shape, it can be reliably positioned and assembled.

  In addition, according to the optical unit manufacturing method of the present invention, the convex piece formed on the non-optical surface of the other optical element is biased against the convex piece formed on the non-optical surface of one optical element. Small optical elements can be easily and accurately assembled without directly touching the optical surface.

  And since the imaging optical system provided with this optical unit has a compact imaging optical system, it is easy to make it smaller and thinner.

  The optical unit of the first embodiment according to the present invention is applied to a camera-equipped mobile phone as an example of an imaging device, and will be described with reference to FIGS. A camera-equipped mobile phone 100 shown in FIG. 1 includes housings 102 and 103 that can be folded in two by a hinge 101. The camera-equipped mobile phone 100 is provided with an imaging window 104 through which a light beam λi from a subject (object) incident on the imaging unit 1 passes at a position that can be seen from the outside with the housings 102 and 103 folded. .

  As shown in FIG. 2, the camera-equipped mobile phone 100 includes an imaging unit 1, an image processing circuit 105 as a processing unit, and a recording unit 106 as a recording unit as main components of an imaging function. A display unit 107 is provided on the outer surface of the opposite housing 102. In addition, operation buttons and the like for performing imaging are provided on an outer surface (not shown) of the housings 102 and 103, for example, a portion that is folded inside and an outer peripheral edge portion of the housings 102 and 103.

  As shown in FIG. 3, the imaging unit 1 includes an optical unit 10, a case 20, an imaging element 30, and a fixed frame 40. The optical unit 10 includes a first optical element 11, a second optical element 12, and a support member 13. The first optical element 11 and the second optical element 12 are one form of the optical element, and are attached with the support member 13 interposed therebetween.

  The first optical element 11 includes a first light incident surface 11a, a first light reflecting surface 11b, and a first light emitting surface 11c. The first optical element 11 is a decentered prism formed in a rotationally asymmetric free-form surface shape in which the first light reflecting surface 11b has one symmetrical surface (mirror image surface). The second optical element 12 includes a second light incident surface 12a, two second light reflecting surfaces 12b and 12c, and a second light emitting surface 12d. The second optical element 12 is a decentered prism formed in a rotationally asymmetric free-form surface shape in which each of the two second light reflecting surfaces 12b and 12c has one symmetrical surface. The symmetry planes of the first optical element and the second optical element are set on the same plane.

  As shown in FIG. 6, the support member 13 includes a diaphragm hole 13a as an opening in a portion sandwiched between the first optical element 11 and the second optical element 12, and also serves as a diaphragm plate. Moreover, the fitting convex part 13b fitted to the case 20 from the inner side is formed at the edge of the support member 13 on the first light incident surface 11a side.

  As shown in FIG. 2, the light beam λi from the object is incident from the first light incident surface 11a, reflected by the first light reflecting surface 11b, and then emitted from the first light emitting surface 11c. The light beam λm emitted from the first optical element 11 passes through the aperture 13a, enters the second optical element 12 from the second light incident surface 12a, and is reflected by the two second light reflecting surfaces 12b and 12c. The light is emitted from the second light exit surface 12d. Then, the light beam λo emitted from the second light emission surface 12d forms an object image on the imaging surface 14. Further, the optical axes of these light beams λi, λm, and λo pass on symmetrical planes set on the first light reflecting surface 11b and the second light reflecting surfaces 12b and 12c, respectively.

  The case 20 holds the optical unit 10 and covers the optical unit 10, and the outer shape is formed in a rectangular parallelepiped box shape that is long in the direction in which the first optical element 11 and the second optical element 12 are arranged. The image plane 14 side is open. In the incident side wall 20a of the case 20 opposite to the imaging surface 14 side, an incident window 21 through which a light beam λi from an object passes and a fitting hole into which a fitting convex portion 13b provided in the support member 13 is inserted. 22 is formed. A cover glass 23 is fitted into the incident window 21.

  In addition, the case 20 is mutually connected along the incident side wall 20a from the corner of the pair of side walls 20b, 20c and the incident side wall 20a provided along the direction in which the first optical element 11 and the second optical element 12 are arranged. A pair of case support pieces 24 extending outwardly away from each other are provided. The case support piece 24 is used when assembling the imaging unit 1, and a case positioning hole 24a penetrating in the thickness direction is provided at the base.

  The image sensor 30 is mounted on the image sensor substrate 31, and the light receiving surface 30 a is disposed on the imaging surface 14. The image sensor 30 is a CCD (Charge-coupled device) in which a large number of semiconductor elements, such as phototransistors, that convert light into electrical signals are arranged on the light receiving surface 30a. On the image sensor substrate 31, an image element IF (interface) circuit or the like that links the image sensor 30 and the image processing circuit 105 is mounted. The imaging element substrate 31 is mounted on the opposite side of the optical unit 10 with respect to the fixed frame 40, and a flexible connector 33 connected to the image processing circuit 105 from the edge on the first optical element 11 side is attached. .

  The fixed frame 40 holds the image sensor substrate 31 on which the image sensor 30 is mounted, has a sufficient size to cover the opening 20d of the case 20, and a position corresponding to the light receiving surface 30a of the image sensor 30. The exit window 41 is formed in the front. The exit window 41 allows the light beam λo emitted from the second light exit surface 12d to pass toward the light receiving surface 30a of the image sensor 30. The fixed frame 40 includes a first support piece 42 and a second support piece 43 which are fixed frame support pieces. The first support piece 42 extends from the end on the second optical element 11 side in the direction in which the first optical element 11 and the second optical element 12 are arranged. The second support pieces 43 extend in a direction away from both ends of the side on the first optical element 11 side, and are provided in a pair. The first support piece 42 and the second support piece 43 are used when the imaging unit 1 is assembled. As for the 1st support piece 42, the fixed frame positioning hole 42a penetrated in a plate | board thickness direction is provided in the base part.

  Further, the fixed frame 40 is positioned outside the first side wall 20e on the first optical element 11 side and the second side wall 20f on the second optical element 12 side of the case 20 at the first side wall 20e and the second side wall 20f. , And a fixing piece 44 extending toward the case 20 side. First adhesive surfaces 25e and 25f are provided on the outer surfaces of the first side wall 20e and the second side wall 20f facing the fixed piece 44, respectively. In the present embodiment, the first bonding surfaces 25 e and 25 f are provided perpendicular to the imaging surface 14 of the optical unit 10. On the fixed piece 44 side, second adhesive surfaces 44e and 44f extending in parallel along the first adhesive surfaces 25e and 25f are provided, respectively. A gap C is formed between the case 20 and the fixed frame 40 as shown in FIGS. 2 and 4 in a state where the imaging surface 14 of the optical unit 10 and the light receiving surface 30a of the image sensor 30 are positioned. Is done.

  The case 20 and the fixed frame 40 are fixed to each other by the first synthetic resin 51 and the second synthetic resin 52 as shown in FIG. 5 while maintaining the gap C. As shown in FIGS. 4 and 5, the first synthetic resin 51 is filled between the first adhesive surfaces 25e and 25f and the second adhesive surfaces 44e and 44f. In the present embodiment, the first synthetic resin 51 is an ultraviolet curable synthetic resin that cures when irradiated with ultraviolet rays that are external factors. In particular, the volume change of expansion or contraction is extremely small when cured. Those are preferred. In general, many UV curable synthetic resins cannot be expected to have sufficient light shielding properties. Therefore, when the gap C between the case 20 and the fixed frame 40 is filled with an ultraviolet curable synthetic resin, stray light incident on the light receiving surface 30a of the image sensor 30 must be prevented from entering from the outside of the case 20. . In the present embodiment, the fixing piece 44 not only has a role of increasing the adhesive strength between the case 20 and the fixing frame 40, but also plays a role of compensating for the lack of light shielding properties when using an ultraviolet curable resin. .

  As shown in FIG. 4, the second synthetic resin 52 is filled so as to close a gap C formed between the edge on the opening 20 d side of the case 20 and the fixed frame 40 facing the second synthetic resin 52. The second synthetic resin 52 is a synthetic resin having a slower curing speed than the first synthetic resin 51. The second synthetic resin 52 is preferably a synthetic resin that is more opaque than the first synthetic resin 51 and has an opaque light shielding property. Further, as the properties of the second synthetic resin 52, it is preferable that the volume change due to curing is extremely small and the adhesive strength is higher than that of the first synthetic resin 51.

  In the imaging unit 1 configured as described above, the case support piece 24, the first support piece 42, and the second support piece 43 are respectively held, and the relative position between the imaging surface 14 and the light receiving surface 30a is optimized. Thus, the positioning adjustment of the case 20 and the fixed frame 40 is performed. After the second synthetic resin 52 is cured, the case support piece 24, the first support piece 42, and the second support piece 43 are cut as shown in FIG. 5, and the outer shape of the imaging unit 1 is a rectangular parallelepiped box shape. It becomes.

  Thus, according to the imaging unit 1 of the present embodiment, the gap C is provided between the case 20 and the fixed frame 40 in a state where the imaging surface 14 is positioned with respect to the light receiving surface 30a. The first synthetic resin 51 and the second synthetic resin 52 are filled in the gap C while maintaining the size of the gap C, and the case 20 and the fixed frame 40 are fixed to each other. The imaging unit 1 can perform fine adjustment with respect to the designed relative positional relationship between the imaging surface 14 and the light receiving surface 30a, and has a simple structure between the imaging surface 14 and the light receiving surface 30a. Positioning can be performed.

  As shown in FIG. 3 and FIG. 4, the first optical element 11 and the second optical element 12 of the optical unit 10 are cut into marks 11m, 11n, and 11f on the side non-optical surfaces 11e, 11f, 12e, and 12f, respectively. 12m, 12n. The non-optical surfaces 11e, 11f, 12e, and 12f are surfaces (optical axis surfaces λ) through which the optical axes of the light beam λi incident on the first light incident surface 11a and the light beam λo emitted from the second light emitting surface 12d pass. It is provided in parallel. The cut marks 11m, 11n, 12m, and 12n are formed on the first convex pieces 11g and 11h provided on the non-optical surfaces 11e and 11f of the first optical element 11 and the second optical element 12, as shown in FIG. The second convex pieces 12g and 12h provided on the non-optical surfaces 12e and 12f are traces cut by the laser beam A in the cutting step S3 (see FIG. 13) in the optical unit manufacturing method described later.

  As shown in FIG. 6, the first convex pieces 11g and 11h are arranged in a pair near the first light exit surface 11c, and the second convex pieces 12g and 12h are arranged in a pair near the second light incident surface 12a. ing. As shown in FIG. 7, the first convex pieces 11g and 11h and the second convex pieces 12g and 12h extend in directions opposite to each other from the optical axis of the light beam λm passing through the aperture 13a. As shown in FIG. 9, the first convex pieces 11g and 11h and the second convex pieces 12g and 12h are on the same plane parallel to the optical axis of the light beam λm and orthogonal to the optical axis surface λ (convex piece arrangement surface α). Is placed on top. The first surface 11i on the first light incident surface 11a side of the first convex pieces 11g and 11h and the second surface 11j opposite to the first surface 11i are a first light reflecting surface from the first light emitting surface 11c side. It is formed in a tapered shape that gradually approaches each other toward the 11b side. The first surface 11i and the second surface 11j serve as reference surfaces for positioning in the optical unit manufacturing method described later. The first surface 11i and the second surface 11j may be provided in parallel with the convex piece arrangement surface α. In this case, the third surface 11k on the first light reflecting surface 11b side is the reference surface.

  Boss 15a, 15b which adjoins toward the 2nd convex piece 12g, 12h is provided in the 1st convex piece 11g, 11h. In a state where the first optical element 11 and the second optical element 12 are positioned with respect to each other, the tips 15c and 15d of the bosses 15a and 15b do not contact the second convex pieces 12g and 12h and have a slight gap d. ing. As shown in FIG. 8, the gap d is shifted between the optical axes of the first optical element 11 and the second optical element 12 even if one of the bosses 15 a and 15 b is in contact with the second convex pieces 12 g and 12 h. The size is set so as to be within the allowable tolerance θ. If the tips 15c and 15d of the bosses 15a and 15b are formed in a spherical shape as shown in FIG. 10, it is easy to set the gap d.

  The bosses 15a and 15b may protrude from the second convex pieces 12g and 12h toward the first convex pieces 11g and 11h, or the first convex pieces 11g and 11h and the second convex pieces 12g and 12h. May be provided so as to approach each other. Further, instead of providing the bosses 15a and 15b, the first convex pieces 11g and 11h and the second convex pieces 12g and 12h may be close to each other with a gap d.

  In the present embodiment, the case where the optical unit 10 is applied to the camera-equipped mobile phone 100 that is an imaging device has been described as an example. However, the present invention is not limited to this, and the optical unit 10 is a digital camera or a camera unit including an imaging device. For example, a compact digital camera or a camera unit can be provided.

When the optical unit 10 of an eccentric optical system is employed as the optical unit incorporated in the imaging unit, the following effects are expected.
(1) A free-form surface having power (refractive power) is used for the three reflecting surfaces. However, these reflecting surfaces can obtain a larger power than a refractive optical system such as a lens. At the same time, it is hardly affected by chromatic aberration.
(2) Seven optical surfaces can be arranged in a compact space. That is, the optical elements can be condensed and set in a limited space.
(3) In order to improve optical performance, it is desirable to lengthen the optical path length of the entire optical system to some extent, but by using such a prism optical system, the optical path length is long by bending the optical path. However, the overall size can be made compact.
As described above, the optical unit 10 is compatible with improving image quality while being compact.

  Next, the optical unit manufacturing method according to the second embodiment of the present invention will be described with reference to FIGS. 11 to 14 by taking as an example a case where it is applied to the optical unit 10 according to the first embodiment. The optical unit manufacturing method of the present embodiment is a range of manufacturing steps in which the first optical element 11 and the second optical element 12 are positioned and fixed integrally with the support member 13 interposed therebetween. Since the optical unit 10 has been described in the first embodiment, the same reference numerals are given and description thereof is omitted.

  The optical unit manufacturing method includes an adhesive application step S1, a positioning step S2, and a cutting step S3. In the adhesive application step S1 and the positioning step S2, the positioning device 260 is used, and in the cutting step S3, the laser cutting device 270 is used. First, the positioning device 260 and the laser cutting device 270 will be described below.

  As shown in FIGS. 11 and 12, the positioning device 260 includes a prism pedestal 261 and a pressing mechanism 262. The prism pedestal 261 and the pressing mechanism 262 are arranged in the vertical direction, and the first optical element 11, the support member 13, and the second optical element 12 are sandwiched therebetween. As described above, the positioning device 260 is provided so as to position the first optical element 11 and the second optical element 12 with the optical axis of the light beam λm passing through the aperture 13a directed in the vertical direction.

  The prism pedestal 261 includes a pair of holding jigs 263 extending upward in the vertical direction from the base. The holding jig 263 is a positioning jig for positioning the first optical element. A cutout 263 b is provided at the upper end 263 a of the holding jig 263. The notch 263b is formed according to the outer shape of the first convex pieces 11g and 11h of the first optical element 11. In the present embodiment, the first surface 11i and the second surface 11j of the first convex pieces 11g and 11h are formed in a tapered shape, and the inner surface of the notch 263b matches the first surface 11i in accordance with the taper angle. It is formed so as to contact the second surface 11j. Since the first convex pieces 11g and 11h are supported by the notch 263b, the first optical element 11 is set on the holding jig 263 with the first light exit surface 11c facing upward.

  The pressing mechanism 262 includes a pressing jig 264 that is disposed above the prism base 261 in the vertical direction and extends downward toward the prism base 261. The pressing jig 264 is a positioning jig for positioning the second optical element. The tip 264a of the pressing jig 264 has second convex pieces 12g and 12h facing the second light reflecting surface 12b of the second optical element 12 set on the positioning device with the second light incident surface 12a facing downward. Abutting on the end face 12i. The end surface 12i serves as a reference surface for positioning the second optical element 12.

The laser cutting device 270 includes a laser irradiation nozzle 271 and a prism clamp 272 shown in FIG. The laser cutting device 270 includes a laser oscillator, a laser transmission path, a clamp inversion mechanism, an air blower, a nozzle positioning mechanism, and the like. As the laser, a CO ₂ laser, a CO laser, a YAG laser, or the like can be applied.

  The prism clamp 272 includes a base portion 273, a presser plate 274, and an air cylinder 275. The base portion 273 is formed with a rib 273a that supports the edge 13c of the support member 13 on the second light exit surface 12d side. The holding plate 274 is formed with a holding portion 274 a that fits with the fitting convex portion 13 b of the support member 13. In the air cylinder 275, the cylinder portion 275a is fixed to the base portion 273, and a presser plate 274 is attached to the tip of the piston 275b.

  The prism clamp 272 drives the air cylinder 275 from the first light incident surface 11a side and the second light emission surface 12d side of the support member 13 to which the first optical element 11 and the second optical element 12 are attached, thereby ribs 273a. And the holding portion 274a. Further, the holding plate 274 is provided with the same width as the support member 13 or slightly wider, and the first optical element 11 and the second optical element 12 are not directly irradiated with the laser light A emitted from the laser irradiation nozzle 271. It also serves as protection for

  The prism clamp 272 can position the optical unit 10 at the focal position of the laser light A emitted from the laser irradiation nozzle 271 so as to cut the bases of the first convex pieces 11g and 11h and the second convex pieces 12g and 12h. Anything is fine. That is, the optical unit 10 can be held and reversed so that the first convex pieces 11g and 11h and the second convex pieces 12g and 12h can be cut without being limited to the above-described configuration shown in FIG. Is preferred. For example, a prism clamp that is driven by a solenoid instead of the air cylinder 275 may be used.

  In order to cut the first convex piece 11h (11g) and the second convex piece 12h (12g) on the opposite side after cutting the first convex piece 11g (11h) and the second convex piece 12g (12h) on one side The clamp reversing mechanism may rotate the optical unit 10 about the vertical axis, may be turned around the horizontal axis, or may move the laser irradiation nozzle 271. Furthermore, the posture of the optical unit 10 in the cutting step S3 may be such that the first optical element 11 and the second optical element 12 are horizontally placed as shown in FIG. 13, or the positioning step shown in FIG. The posture of S2 may be maintained.

The procedure of the optical unit manufacturing method constructed using the positioning device 260 and the laser cutting device 270 described above will be described based on the flowchart shown in FIG.
The adhesive application step S1 and the positioning step S2 are performed in parallel. First, the first convex piece is fitted into the notch 263b of the holding jig 263, and the first optical element 11 is set on the prism base 261 (S10). Next, an appropriate amount of adhesive is applied to the first light emitting surface 11c of the first optical element 11 by the dispenser 266 (S20). After the dispenser 266 is retracted to a position where it does not get in the way, the support member 13 is placed on the first optical element 11 (S30).

  The dispenser 266 is brought close again, and an appropriate amount of adhesive is applied to the support member 13 in a range where the second light incident surface 12a comes into contact (S40). When the adhesive is applied, the dispenser 266 is retracted, and the second optical element 12 is placed on the support member 13 (S50). The pressing mechanism 262 is approached from above, and the second convex pieces 12g and 12h are urged toward the first convex pieces 11g and 11h by the tip 264a of the pressing jig 264 (S60). The contact surfaces of the first optical element 11 and the support member 13 and the support member 13 and the second optical element 12 are pressed against each other so that the first optical element 11 and the second optical element 12 are positioned. Is formed.

  As shown in FIG. 11, the first optical element 11 and the second optical element 12 are cured in a state where the first optical element 11 and the second optical element 12 are biased so as to sandwich the support member 13. The optical element 12 is integrated with the support member 13 interposed therebetween. An adhesive having a sufficient curing time that does not cure until the second optical element 12 is pressed by the pressing jig 264 is used.

  For the adhesive, the curing speed can be adjusted by an external factor. For example, when an ultraviolet curable adhesive is used, the time until the adhesive is cured can be positively adjusted. Accordingly, it is easy to adjust the timing for curing the adhesive. As external factors for adhesives, it is possible to apply temperature, oxygen, gas that promotes curing of adhesives, moisture in the air, etc. in addition to ultraviolet rays, and adhesives can be selected accordingly. Is possible.

  The adhesive application step S1 may be performed in advance without being performed in parallel with the positioning step S2, or may be performed later in the state shown in FIG. In this case, the adhesive is injected from the side by the dispenser 266. In this case, it is preferable that the adhesive is low in viscosity and easily spread (capillary) between the first optical element 11 and the support member 13 and between the support member 13 and the second optical element 12 by capillary action.

  When the adhesive is cured and the first optical element 11 and the second optical element 12 are fixed to the support member 13, the optical unit 10 is removed from the positioning device 260 (S70), and the process proceeds to the cutting step S3. To do. In the cutting step S3, first, as shown in FIG. 13, the support unit 13 is held by the prism clamp 272, whereby the optical unit 10 is mounted on the laser cutting device 270 (S80). In this state, as shown in FIG. 13, the first convex pieces 11g and 11h and the second convex pieces 12g and 12h are cut (S90). In the cutting step S3, instead of cutting with the laser beam A, the first convex pieces 11g, 11h and the second convex are made with a wire cutter in which abrasive grains are attached to a steel wire or a disk cutter in which abrasive grains are attached to a disk. The pieces 12g and 12h may be cut.

  The optical unit 10 from which the first convex pieces 11g and 11h and the second convex pieces 12g and 12h have been cut is then housed in the case 20 as shown in FIG. 4 (S100). The case 20 is positioned (S110) and fixed to the fixed frame 40 to which the image sensor 30 is attached (S120) so that the imaging surface 14 of the optical unit 10 coincides with the light receiving surface 30a of the image sensor 30. After the second synthetic resin 52 is cured (S130), the case support piece, the first support piece, and the second support piece are cut (S140), and the imaging unit 1 shown in FIG. 5 is completed.

  According to the optical unit manufacturing method described above, the first and second convex pieces 11g and 11h and the second convex pieces 12g and 12h for positioning and holding are provided in advance on the first optical element 11 and the second optical element 12 that are optical elements. After the first optical element 11 and the second optical element 12 are positioned and fixed, the first convex pieces 11g and 11h and the second convex pieces 12g and 12h are cut and removed. Even when is small, it is excellent in handling property and can be positioned easily and accurately.

  Further, the optical unit 10 of the present invention forms the first convex pieces 11g and 11h on the non-optical surfaces 11e and 11f of the first optical element 11, and the second convex on the non-optical surfaces 12e and 12f of the second optical element 12. Since the pieces 12g and 12h are formed and the first optical element 11 and the second optical element 12 are positioned using the first convex pieces 11g and 11h and the second convex pieces 12g and 12h, the first optical element 11 And even if the 2nd optical element 12 becomes small, positioning can be performed accurately. The first convex pieces 11g and 11h and the second convex pieces 12g and 12h are cut and removed after the first optical element 11 and the second optical element 12 are positioned and fixed to each other. Does not restrict

  By incorporating the imaging unit 1 including the optical unit 10, it is possible to provide an imaging device such as a digital camera or a camera-equipped mobile phone 100 that is reduced in size and thickness and has high performance.

  The optical unit according to the present invention is applied to an imaging unit of a medical or industrial endoscope, a telescope having an imaging function built in together with an imaging element, in addition to being applied to an imaging unit of a digital camera or a camera-equipped mobile phone. It can be used as an optical unit for observation systems such as binoculars.

1 is a perspective view showing a camera-equipped mobile phone according to a first embodiment of the present invention. The block diagram which shows typically the main structures of the imaging function of the mobile telephone with a camera shown in FIG. FIG. 2 is an exploded perspective view of the imaging unit illustrated in FIG. 1. Sectional drawing which assembled the imaging unit shown in FIG. The perspective view of the state which cut out the case support piece of the imaging unit shown in FIG. 4, and the 1st and 2nd support piece. FIG. 4 is an exploded perspective view of the optical unit shown in FIG. 3. The top view which looked at the optical unit shown in FIG. 6 from the 1st light-incidence surface side. FIG. 8 is a plan view showing a state in which the optical axis of the first optical element and the second optical element of the optical unit shown in FIG. 7 are shifted within an allowable tolerance. The side view of the optical unit shown in FIG. The perspective view of the other form of the boss | hub provided in the 1st convex piece of the 1st optical element shown in FIG. The perspective view in the state where the 1st optical element, the 2nd optical element, and the supporting member are positioned by the positioning device used in the optical unit manufacturing method of a 2nd embodiment concerning the present invention. FIG. 12 is an exploded perspective view in which the positioning device and the optical unit shown in FIG. 11 are developed in the vertical direction. The perspective view in the state where the 1st convex piece and the 2nd convex piece of an optical unit are cut | disconnected by the laser cutting device used in the optical unit manufacturing method of 2nd Embodiment which concerns on this invention. The flowchart of the optical unit manufacturing method of 2nd Embodiment which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Imaging unit, 10 ... Optical unit, 11 ... 1st optical element (optical element), 11a ... 1st light-incidence surface (light-incidence surface), 11b ... 1st light-reflection surface (light anti-slope), 11c ... 1st 1 light exit surface (light exit surface), 11e, 11f ... non-optical surfaces, 11g, 11h ... first convex piece, 11i ... first surface (reference surface), 11j ... second surface (reference surface), 12 ... first 2 optical elements (optical elements), 12a ... second light input surface (light incident surface), 12b, 12c ... second light reflecting surface (light reflecting surface), 12d ... second light emitting surface (light emitting surface), 12e , 12f ... non-optical surface, 12g, 12h ... second convex piece, 12i ... end face (reference surface), 13 ... support member, 13a ... stop aperture (opening), 14 ... imaging surface, 15a, 15b ... boss, DESCRIPTION OF SYMBOLS 30 ... Image pick-up element, 30a ... Light-receiving surface, 100 ... Cell-phone with camera (imaging device), 105 ... Image processing circuit ( ,..., Recording unit (recording unit), 263... Holding jig (positioning jig), 264... Pressing jig (positioning jig), .lamda.i, .lamda.m, .lambda.o. Projection piece arrangement surface, S1... Adhesive application step, S2. Positioning step, S3.

Claims (14)

In an optical unit in which two optical elements are integrally fixed with a support member having an opening formed therebetween,
The optical element is formed in a light incident surface, a light reflecting surface, a free-form surface and is formed into at least one light reflecting surface, other non-optical surfaces, and at least one formed protruding from the non-optical surfaces. Two convex pieces,
The convex unit is used when the two optical elements are relatively positioned, and is cut and removed after the two optical elements are fixed to each other.   The optical unit according to claim 1, wherein the opening is a stop disposed between the two optical elements.   The optical unit according to claim 1, wherein the optical element is formed by injection molding, and a gate for injecting a synthetic resin is provided on at least one of the convex pieces.   The optical unit according to claim 1, wherein the optical element is formed by injection molding, and the convex piece receives an ejector pin that removes the optical element from a mold.   The optical unit according to claim 1, wherein the convex piece of at least one of the optical elements is provided with a boss that is close to the convex piece of the other optical element.   With the two optical elements positioned relative to each other, the convex piece of one of the optical elements and the convex piece of the other optical element are arranged on the same plane parallel to the optical axis passing through the opening. The optical unit according to claim 1, wherein:   In a state of being positioned relative to the two optical elements, the convex piece of one of the optical elements and the convex piece of the other optical element are arranged on a plane along the direction in which the two optical elements are arranged. The optical unit according to claim 1.   The optical unit according to claim 1, wherein each of the convex pieces has a reference surface that abuts a positioning jig for relatively positioning the two optical elements. A first optical element that emits the light beam from the first light exit surface after the light beam from the object is incident from the first light incident surface and reflected by at least one first light reflecting surface having a free-form surface; ,
The light beam emitted from the first light emission surface is incident from the second light incident surface and reflected by the at least one second light reflection surface having a free-form surface, and then the light beam from the second light emission surface. A second optical element that emits
A support member in which an opening is formed and disposed between the first light exit surface and the second light incident surface, and the first optical element and the second optical element are integrally fixed by an adhesive. When,
A first convex piece formed to protrude from a pair of non-optical surfaces other than the first light incident surface, the first light reflecting surface, and the first light exit surface of the first optical element;
A second convex piece formed to protrude from a pair of non-optical surfaces other than the second light incident surface, the second light reflecting surface, and the second light emitting surface of the second optical element;
The first convex piece and the second convex piece are used for relative positioning of the first optical element and the second optical element, and are cut after the adhesive is cured. unit. In an optical unit manufacturing method in which two optical elements are fixed integrally with a support member having an opening through which a light beam passes.
An adhesive application step of applying an adhesive between the optical element and the support member, and
The convex piece formed on the non-optical surface of one of the optical elements is held, and the convex piece formed on the non-optical surface of the other optical element is sandwiched with the support member interposed therebetween. A positioning step for biasing toward the
And a cutting step of cutting the convex pieces of the two optical elements after the two optical elements are fixed to the support member.   The optical unit manufacturing method according to claim 10, wherein in the cutting step, the convex portion is cut using a laser beam.   The optical device according to claim 10, wherein the positioning step is performed by arranging the two optical elements in a state in which a direction along an optical axis of a light beam passing through the opening is arranged in a vertical direction. Unit manufacturing method.   The optical unit manufacturing method according to claim 10, wherein one of the convex pieces and the other convex piece do not contact each other in a state where the two optical elements are positioned with respect to each other. An optical unit according to claim 1;
An image sensor for converting an object image formed by the imaging optical system into an electric signal by arranging a light receiving surface on an imaging surface of an imaging optical system including the optical unit;
Processing means for performing predetermined electrical processing on the electrical signal obtained from the imaging device to obtain image data;
An imaging apparatus comprising: a recording unit that records the image data from the processing unit on an applied information recording medium.

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