JP2015022011A - Optical device and optical component holding member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce protrusion of a liquid adhesive onto a lens surface when fixing an optical component of an optical device to an optical component holding member with the liquid adhesive.SOLUTION: In an optical device including an optical component holding member which has a holding part for holding an optical component, an adhesive holding part comprises a notch or a slit for interposing an adhesive between the holding part of the optical component holding member and the optical component, and a part of the holding part of the optical component holding member has a convex shape being in contact with or proximity to the optical component, and the adhesive holding part and the convex shape have a substantially continuous shape.

Description

  The present invention relates to a photographing apparatus such as a video camera, a digital still camera, and a silver salt still camera, an optical apparatus such as a binocular, a telescope, and a field scope, and a lens holding member in the optical apparatus.

  Optical devices such as video cameras and surveillance cameras have responded by increasing the size of lenses used in optical devices and increasing the number of lenses in order to improve image quality and performance. However, in recent years, further reduction in size and weight has been demanded, and it has become necessary to reduce the thickness of the lens in the optical apparatus and improve the mounting position accuracy in order to achieve both of these requirements. As in Patent Document 1 and Patent Document 2, the fixing of the lens in the optical apparatus is a method of fixing to a lens fixing member having thermoplasticity by heat caulking, or a solid auxiliary material in which plasticity or adhesiveness is generated by infrared rays or heat. A method of fixing using is known. Further, a method of fixing using a liquid adhesive that is cured by ultraviolet rays and generates a holding force is also widely known.

  However, as in Patent Document 1 and Patent Document 2, when directly caulking the lens fixing member or fixing using a solid auxiliary material, it is necessary to strongly press the lens to improve the mounting accuracy. Arise. For this reason, there has been a problem that the lens is distorted due to a large stress during the mounting, and can be mounted while being distorted. In particular, in the case of a thin lens in recent years, this is remarkable and there is a problem that desired optical performance cannot be obtained.

  In order to solve this problem, there is a method of using a liquid adhesive that causes a chemical reaction with ultraviolet rays or the like and generates a holding force. When the liquid adhesive is used, the adhesive, which is a fluid, moves with time and contacts the lens and the lens fixing member without pressing the lens strongly, and can be fixed without using a large stress. However, since the liquid adhesive is a fluid, the liquid adhesive wraps around and sags and moves to a place other than the desired bonding location, resulting in, for example, a dirty lens surface. In addition, when the liquid adhesive is, for example, an ultraviolet curable adhesive, a part of the adhesive after moving the fluid does not receive the ultraviolet light necessary for curing, leaving uncured adhesive remaining and causing problems such as lens contamination due to outgassing. Has a problem to cause. In Patent Document 3, this problem is addressed by forming a flange convex portion on the flange portion of the lens having the flange portion. However, the flange convex part of Patent Document 3 requires a flange structure in the lens, and when the lens material is made of glass, it is not easy to make such a shape, and there is a problem that the cost increases.

JP-A-10-96842 JP 2012-048271 A JP 2009-47820 A

  It is an object of the present invention to provide an optical device and an optical component holding member capable of reducing the adhesive from sagging on the lens surface when the optical component of the optical device is fixed to the optical component holding member with a liquid adhesive. Objective.

  A configuration for achieving the above object is to provide an adhesive between an optical component holding member and an optical component in an optical device having an optical component holding member having a holding portion for holding the optical component. When the adhesive holding part composed of notches or slits and a part of the holding part of the optical component holding member have a convex shape in contact with or close to the optical component, the adhesive holding part and the convex shape are An optical apparatus having an optical component holding member characterized by having a substantially continuous shape.

  ADVANTAGE OF THE INVENTION According to this invention, when fixing the optical component of an optical apparatus to an optical component holding member with a liquid adhesive agent, it can reduce that an adhesive agent droops on a lens surface.

1 is a block diagram of an optical apparatus according to an embodiment of the present invention. The perspective view of the optical component in connection with embodiment of this invention and an optical component holding member is shown. 1 is an exploded perspective view of an optical component and an optical component holding member according to an embodiment of the present invention. The fragmentary enlarged view of the optical component holding member concerning embodiment of this invention is shown. The fragmentary enlarged view of the optical component holding member concerning embodiment of this invention is shown. 1 shows an optical component and an optical component holding member according to an embodiment of the present invention. The adhesion schematic diagram of the optical component and optical component holding member concerning the embodiment of the present invention is shown. The cross section of the adhesion schematic diagram of the optical component in connection with embodiment of this invention and an optical component holding member is shown. The perspective view of the optical component in connection with embodiment of this invention and an optical component holding member is shown. 1 is an exploded perspective view of an optical component and an optical component holding member according to an embodiment of the present invention. The fragmentary enlarged view of the optical component holding member concerning embodiment of this invention is shown. The cross section of the adhesion schematic diagram of the optical component in connection with embodiment of this invention and an optical component holding member is shown. The fragmentary enlarged view of the optical component holding member concerning embodiment of this invention is shown.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram of an imaging apparatus as an optical apparatus according to Embodiments 1 and 2 of the present invention. The imaging device includes a digital video camera, a digital still camera, a surveillance camera, and the like.

  In FIG. 1, L1 is a first lens unit having a positive refractive power that is fixed during zooming. L2 is a second lens unit having a negative refractive power as a first variable power lens group (zoom lens group) that performs a variable power operation by moving in the optical axis direction indicated by an arrow. L3 is a third lens unit having a fixed positive refractive power. L4 is a fourth lens group as a focus lens group having a positive refractive power that performs focus adjustment by moving in the optical axis direction indicated by the arrow. The first lens unit L1 to the fourth lens unit L4 constitute an imaging optical system and an optical axis.

  Reference numeral 1 denotes a front lens barrel that holds the first lens unit L1. Reference numeral 2 denotes a zoom lens holding frame as a first moving member that holds the second lens unit L2, and is supported by two guide bars (not shown) so as to be movable in the optical axis direction. Reference numeral 3 denotes a fixing member that holds the third lens unit L3. Reference numeral 4 denotes a focus lens holding frame as a second moving member that holds the fourth lens unit L4. The second focus lens holding frame is fixed with a substantially square cylindrical air core coil 10 and an invisible flexible printed circuit board for energizing the coil 10. Reference numeral 8 denotes a zoom motor as drive means (actuator) for driving the second lens unit L2. The lead screw 8a serving as a feed screw meshes with a rack member 7 installed on a first zoom lens holding frame that is guided and held so as to freely move in the optical axis direction. The lens holding frame moves in the optical axis direction. The lead screw 8a is arranged coaxially with the rotor constituting the zoom motor 8 and parallel to the optical axis. Reference numeral 9 denotes a zoom initial position sensor, which includes a photo interrupter. The zoom initial position sensor 9 electrically detects the switching between light shielding and light transmission due to movement in the optical axis direction of a light shielding unit (not shown) formed on the first zoom lens holding frame, and holds the first zoom lens. The origin (reference position) of the optical axis direction of the frame is detected. Reference numeral 6 denotes an aperture device that changes the aperture diameter of the optical system, and is a guillotine aperture device that changes the aperture diameter by moving two aperture blades in opposite directions by the drive unit 6.

  Reference numeral 34 denotes an aperture sensor that detects the rotational position of the drive magnet of the aperture drive unit 6 with a Hall element. The imaging means 30 comprising a CCD or CMOS, a low-pass filter, an infrared cut filter, etc. is fixedly held by a rear barrel when not shown. The imaging means 30 photoelectrically converts an optical image formed by the photographing optical system to generate a photographing signal and outputs it to the camera signal processing circuit 31. The yokes 11 and 12 and the magnet 13 are fixed to the rear barrel. The yoke 11 has a U-shaped cross section and extends in the optical axis direction. A magnet 13 is held inside the yoke 11. An air core portion of the coil 10 is inserted into the yoke 11, and the coil 10 is separated from the yoke 11 and the magnet 13. The magnet 13 is magnetized in a direction perpendicular to the optical axis and extends in the optical axis direction. A yoke 12 is held at the open end of the yoke 11. The coil 10, the yokes 11 and 12, and the magnet 13 constitute a voice coil motor (VCM or linear actuator). The second moving member is configured to be movable in a predetermined direction (optical axis direction) by the voice coil motor.

  The camera signal processing circuit 31 performs signal processing such as predetermined amplification and gamma correction on the output of the imaging means 30. The signal processed by the camera signal processing circuit 31 is output to a microcomputer 32. The microcomputer 32 takes in many signals and performs signal processing. In addition, a large number of signals are output in accordance with the input signal to control the optical device. For example, the microcomputer 32 outputs an aperture driving signal output to the aperture driving means in accordance with an input signal from the camera signal processing circuit 31 and an input signal such as the rotation amount of the aperture driving unit from the aperture sensor 34 to adjust the light amount. Do. Reference numeral 33 denotes a recording means for recording an image signal processed by the microcomputer 32 and other recording conditions. 50 is a zoom switch for instructing a zooming operation, 51 is a focus switch for instructing a manual focus operation (focusing operation) consciously by the photographer, and 52 is a power switch. When the power switch 52 is turned on, the zoom motor 8 receives a drive signal from the zoom drive circuit 35 by a signal from the microcomputer 32. Then, the initial position is detected by the photo interrupter 9, and the first zoom lens holding frame moves to a predetermined position and stands by. The zoom motor 8 is subjected to position control corresponding to the operation of the zoom switch 50 by the number of steps from the initial position. When the zoom switch 50 is operated, the microcomputer 32 determines in which direction the movement direction is operated, and the zoom operation is performed.

  On the other hand, when the coil 10 is energized from the focus drive circuit 36, the second focus lens holding frame is driven in the optical axis direction by the action of the magnetic circuit constituted by the yokes 11, 12 and the magnet 13. The second focus lens holding frame detects the detected surface of the scale 20 having a detection surface fixed to the second focus lens holding frame with an adhesive and the scale 20 mechanically fixed to the rear barrel 101. The position of the second focus lens holding frame is detected by the sensor 21 that generates an electrical signal. In the present invention, as a position detection mechanism, a groove or pattern is formed on a glass or a silicon wafer so that reflection or interference intensity is generated as an optical encoder capable of emitting and receiving LEDs as a sensor 21 and a scale 20 in order to have highly accurate position resolution. Is used.

  FIG. 2 is a perspective view of a focus lens holding frame 4 as an optical component holding member and a focus lens L4 as an optical component for explaining the first embodiment of the present invention. OX indicates the center of the optical axis of the optical device. FIG. 3 is an exploded perspective view of FIG.

  2 and 3, the lens holding member 4 is provided with an inner peripheral frame 403 as an optical component holding portion which is larger than the outer shape of the focus lens L4 and formed in substantially the same shape, and a body for supporting the focus lens in the optical axis direction. Part 405. Further, a part of the inner peripheral frame 403 is cut out, and three adhesive grooves 401 as adhesive holding portions are formed. 4 is an enlarged view of the adhesive groove 401 and the lens holding frame 403 in FIG.

  FIG. 5 is an enlarged view of the adhesive groove 401 and the lens holding frame 403 in FIG.

  4 and 5, the inner peripheral frame 403 is provided with a convex shape as a lens correction surface 404 for determining the position of the focus lens L4 with respect to a surface orthogonal to the optical axis of the optical device. It can also be seen that the lens correction surface 404 is formed continuously from the adhesive groove 401.

  FIG. 6 is a view of the lens holding member as seen from the optical axis direction in order to better understand the lens correction surface 404 according to the first embodiment of the present invention.

  According to FIG. 6, it can be seen that the lens correction surface 404 is formed so that the central axis Q2 that is closer to the optical axis center OX of the optical device than the central axis Q1 formed by the inner peripheral frame 403 is formed by three surfaces.

  Thus, the focus lens L4 is placed in the inner peripheral frame 403, the optical axis of the optical device and the optical axis center of the focus lens L4 are substantially determined by the lens correction surface 404, and the position in the optical axis direction is approximately determined by the body portion 405. It is determined. In this state, it is integrally fixed by the adhesive 402 put in the adhesive groove 401. FIG. 7 is a schematic diagram of the injection of the adhesive 402 in FIG. 5, and is a process in which the adhesive is injected into the adhesive groove 401 from a syringe 500 as an adhesive injection tool.

  FIG. 8 is a cross-sectional view taken along a broken line D in FIG.

  According to FIGS. 7 and 8, when the adhesive 402 is put into the adhesive holding part 401, the adhesive 402 spreads uniformly on the adhesive holding part 401 due to the flow of the liquid and comes into contact with the focus lens L4. Thereafter, the adhesive 402 continues to be put into the adhesive holding portion 401. At this time, as the adhesive increases, the weight of the adhesive increases, and the inflow pressure R that tends to flow into the gap 406 between the focus lens L4 and the adhesive holding portion 401 increases.

  On the other hand, in the first embodiment of the present invention, since the adhesive groove 401 and the lens correction surface 404 are continuous, the gap 406 between the focus lens L4 and the adhesive groove 401 is narrowed. Accordingly, the inflow pressure necessary for the adhesive 402 to flow into the gap 406 becomes high, and as a result, the flow can be reduced. As described above, in the embodiment of the present invention, since the adhesive groove 401 and the convex lens correction surface 404 are continuous, the gap between the focus lens L4 and the adhesive groove 401 is narrowed so that the adhesive does not easily flow. ing.

  FIG. 9 is a perspective view of a lens holding frame 4 as an optical component holding member and a focus lens L4 as an optical component for explaining the second embodiment of the present invention. OX indicates the center of the optical axis of the optical device. FIG. 10 is an exploded perspective view of FIG.

  9 and 10, the lens holding member 4 has an inner peripheral frame 403 as an optical component holding portion which is made larger than the outer shape of the focus lens L4 and substantially the same shape, and a body for supporting the focus lens in the optical axis direction. Part 405. Further, it can be seen that a part of the inner peripheral frame 403 is cut out to form three adhesive grooves 410 as first adhesive holding portions.

  FIG. 11 is a partially enlarged view of the adhesive groove 410. The adhesive groove 410 is provided with a slit 411 at a position facing the focus lens L4, and further provided with an adhesive relief groove 412 as a second adhesive holding portion across the slit. It has been. The width of the slit 411 is designed to be larger than the gap 406 between the focus lens L4 and the lens correction surface 404. In addition, the slit 411 and the adhesive relief groove 412 are opened so that light necessary for curing the photocurable adhesive can be irradiated. In particular, the slit 411 has an inclined surface 413.

  FIG. 12 is a schematic diagram of the injection of the adhesive 402 in FIG. 9. The focus lens L4 is placed in the inner peripheral frame 403, and the optical position is substantially determined by the lens correction surface 404 and the invisible body 405 in the figure. Is done. Thereafter, in order to integrally fix the focus lens L4 with the lens holding frame 4, a photocurable adhesive is injected into the adhesive groove 410 from the syringe 500 as an adhesive injection tool. At this time, as the photocurable adhesive increases, the weight of the photocurable adhesive increases, and the inflow pressure R that tends to flow into the gap 406 between the focus lens L4 and the adhesive holding portion 401 increases. On the other hand, an equivalent inflow pressure R is also applied to the slit 411. At this time, since the width of the slit 411 is designed to be larger than the gap 406 between the focus lens L4 and the lens correction surface 404, the photocurable adhesive flows into the gap 406. This makes it difficult to flow into the slit 411 first and into the gap 406.

  Thus, in the second embodiment of the present invention, as shown in FIG. 12, when a certain amount or more of the adhesive is injected, it is difficult to flow into the gap 406 which flows into the slit 411 and is difficult to perform light irradiation. In order to make it easier to understand the first embodiment of the present invention, the second embodiment of the present invention, the implementation of the present invention, and the effects thereof, the adhesive groove and the lens correction surface have been described in a continuous form. However, as shown in FIG. Even in a continuous form, the effect of the present invention, that is, the amount of the adhesive flowing between the lens and the lens holding member can be reduced and is within the scope of the claims.

L4 Focus lens L4a Focus lens chamfer OX Optical axis center of optical equipment

Claims (4)

In an optical apparatus having an optical component holding member having a holding portion for holding an optical component,
An adhesive holding part constituted by a notch or a slit for interposing an adhesive between the holding part of the optical component holding member and the optical part;
When a part of the holding part of the optical part holding member has a convex shape that is in contact with or close to the optical part, the adhesive part holding part and the convex shape are a continuous shape. An optical apparatus having a member.   A convex shape in which a part of the holding portion of the optical component holding member is in contact with or close to the optical component is a lens correction surface that determines a position when the optical component is fixed to the optical component holding member. An optical apparatus having the optical component holding member according to claim 1.   The adhesive holding portion of the optical component holding member has one or more slits or notches at positions different from those other than the convex shape portion continuous with the adhesive holding portion, and one of the slits or notches. The optical device having an optical component holding member according to claim 1 or 2, wherein one is larger than a gap generated between the adhesive holding portion and the optical component. The optical apparatus having an optical component holding member according to any one of claims 1 to 3, wherein the adhesive is liquid before curing.