JP2009216946A - Photographing lens unit and digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photographing lens unit for accurately positioning the optical axis of liquid crystal lens applied to a photographing lens unit. <P>SOLUTION: The photographing lens unit includes a liquid crystal lens section having the optical axis and provided with a liquid crystal layer 62 and transparent electrode plates 56 and 61 arranged on the front and back surfaces in the optical axis direction, and an inner frame 54 as a liquid crystal lens holding member for holding the liquid crystal lens section inside it. The outer periphery of the transparent electrode plate 56 on the front side of the liquid crystal lens section is butted on positioning projections 54g and 54h disposed in the inner periphery of the inner frame 54 to be positioned, thereby accurately positioning the optical axis of the liquid crystal lens section to the inner frame 54. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a photographing lens unit in which a liquid crystal lens including a plurality of transparent electrode plates is incorporated, and a digital camera to which the photographing lens unit is applied.

  Conventionally, as a focusing mechanism for changing the focal length or the focal position of a camera, a method of focusing by combining a plurality of lenses and changing the positional relationship has been widely used. However, this method requires a lens advancing / retracting drive mechanism, so that there is a drawback that the mechanism becomes complicated, or that a lens driving motor requires a relatively large amount of power. Therefore, as a focusing mechanism that does not require a lens driving mechanism, methods of focusing by changing the refractive index of a liquid crystal lens have been proposed in Patent Documents 1 and 2 and the like.

However, when the temperature of the liquid crystal lens is lowered, the response speed of the refraction characteristics is lowered and it becomes difficult to perform quick focusing when photographing in a low temperature environment, which may cause a problem in camera operation. Therefore, in the liquid crystal lens disclosed in Patent Document 3, a heater electrode for directly heating the liquid crystal layer is provided in a region outside the phase modulation electrode for changing the refractive index of the liquid crystal lens, and the liquid crystal layer is brought to a desired temperature or higher. It is related with the technique which can perform a focusing operation | movement with sufficient speed | velocity in practical use by maintaining.
JP 2006-243572 A JP 2006-209122 A JP 2007-248985 A

  In the electronic apparatus using the liquid crystal lens disclosed in Patent Document 1 described above, the liquid crystal lens having a rectangular transparent substrate used for the optical lens is disposed so that the center of the transparent substrate coincides with the optical axis of the optical lens. In the case of forming a positioning hole in the transparent substrate and aligning the optical axes of the single lens or multiple lenses arranged on the incident side or the exit side, the accuracy of the positioning hole is not necessary for the field of the glass material that is the transparent substrate. Is low and the cost is high due to drilling. In addition, in the electronic device using the liquid crystal lens disclosed in Patent Document 3 described above, when the user uses it, when the external environment falls below a predetermined temperature, the electric power for heating the liquid crystal lens is used. It is necessary and power consumption of the built-in battery is unavoidable.

  The present invention has been made in order to solve the above-described problems. In order to prevent the heat retaining heat around the liquid crystal lens from being affected by the external temperature, the liquid crystal lens is warmed and the transparent electrode plate is used. A photographic lens unit and a photographic lens unit for aligning the optical axes of a single lens or a plurality of lenses arranged on an incident side or an exit side using positioning means provided by a positioning projection provided on a lens frame member. To provide digital. Also, in the imaging lens unit, a liquid crystal lens is applied, and the operating heat of other electrical control elements (for example, when the external environment falls below a predetermined temperature when used by the user, the imaging element is driven in a dummy manner. An imaging lens unit capable of heating the liquid crystal lens using heat generated by an imaging device) and a digital camera using the imaging lens unit are provided.

  A photographic lens unit according to claim 1 of the present invention covers a photographic lens including a liquid crystal lens provided with a plurality of transparent electrode plates, a lens frame member holding the liquid crystal lens therein, and an outer periphery of the lens frame member. The lens frame member includes an optical axis of the liquid crystal lens and an outer peripheral portion of the transparent electrode plate in a plane orthogonal to the optical axis. Positioning means for positioning by positioning protrusions provided on the lens frame member is provided, and the liquid crystal lens can be easily inserted into the lens frame member, thereby enabling simple positioning.

  The photographic lens unit according to a second aspect of the present invention is the photographic lens unit according to the first aspect, wherein the transparent electrode plate is positioned on one outer peripheral portion of the transparent electrode plate by the positioning means.

  According to a third aspect of the present invention, there is provided a photographing lens unit according to the first aspect, further comprising: an imaging element that converts a subject image captured via the photographing lens into an electrical signal; and the imaging element. A liquid crystal driving circuit connected to the transparent electrode plate is mounted on the printed board.

  The photographic lens unit according to a fourth aspect of the present invention is the photographic lens unit according to the first to third aspects, wherein the image sensor is held by the heat dissipating member and the light together with the image sensor with respect to the unit frame member. The unit frame member is supported so as to be movable in a direction perpendicular to the axis, and the unit frame member is engageable with a metal wire provided on the lens frame member or a radiator plate engaging portion connected to a ring plate. A joint is provided.

  A digital camera according to a fifth aspect of the present invention includes the photographing lens unit according to the first aspect and a liquid crystal display unit.

  According to a sixth aspect of the present invention, in the digital camera according to the fifth aspect, the photographing lens unit is replaceable with the digital camera, and the photographing lens unit includes an autofocus optical system, The lens frame member that holds the liquid crystal lens and the lens therein, and the digital camera further includes a finder optical.

  A digital camera according to a seventh aspect of the present invention is the digital camera according to the sixth aspect, wherein the focus detection optical system includes a heat insulating member interposed between the lens frame member and the camera body. The transparent electrode plate is formed by positioning means including a positioning projection provided on the lens frame member with respect to the lens frame member in a plane orthogonal to the optical axis of the condenser lens and the optical axis of the condenser lens. It is positioned through the outer peripheral part.

  According to the present invention, it is possible to retain the temperature of the liquid crystal lens applied to the photographing lens, and to photograph the optical axis of the liquid crystal lens disposed on the incident side or the emission side more accurately. It is possible to provide a lens unit and a digital camera to which the photographing lens unit is applied. An imaging lens capable of heating a liquid crystal lens using operating heat of other electronic control elements (for example, heat generated by the imaging element by dummy driving the imaging element) when the external environment falls below a predetermined temperature. It is possible to provide a unit and a digital camera to which the imaging lens unit is applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view on the optical axis in a retracted state of a lens barrel that is a photographing lens unit according to the first embodiment of the present invention. FIG. 2 is a longitudinal sectional view on the optical axis of the lens barrel of FIG. FIG. 3 is a cross-sectional view of a liquid crystal lens unit applied to the lens barrel of FIG. FIG. 4 is an exploded perspective view of the liquid crystal lens unit of FIG. FIG. 5 is a view of a state in which the liquid crystal lens is inserted and positioned in the middle frame in the liquid crystal lens unit of FIG. 3 as viewed from the back side.

  The optical axis of the photographing lens is indicated by “O” in the figure. In the following description, the subject side of the optical axis is defined as the front side, and the imaging side (image sensor side) is defined as the rear side. Furthermore, the rotation direction of the cam barrel of the lens barrel is indicated by the rotation direction viewed from the front side. Further, among the directions orthogonal to the optical axis, the direction perpendicular to the paper surface of FIG. 1 is defined as the X direction, and the vertical direction is defined as the Y direction.

  The lens barrel 1 of the present embodiment can be switched between a photographing enabled state in which zooming and focusing are performed with the length in the optical axis direction extended and a non-photographing state shortened from the extended state, for example, a retracted state. This is a lens barrel that can change the focal length by a liquid crystal lens, and is incorporated in a digital camera.

  As shown in FIGS. 1 and 2, the lens barrel 1 is fixedly supported by a fixed frame support 12 that is a unit frame member supported by a camera body (not shown) and a front surface portion of the fixed frame support 12. A cylindrical fixed frame 2, a printed circuit board 36 that is an imaging device substrate fixed to the back surface of the fixed frame support 12, an optical filter 15 supported by the fixed frame support 12, and the printed circuit board 36 on the XY plane. And an imaging unit 34 including the imaging device 14 supported by the imaging device support plate 37 in a movable state, and a rectilinear frame 3 supported by the fixed frame 2 so as to be movable back and forth in the optical axis direction. The cam cylinder 5 supported by the fixed frame 2 and rotated and moved forward and backward in the direction of the optical axis O, and the cam cylinder / second group frame linear guide float float-restricted by the fixed frame 2 and moved forward and backward together with the cam cylinder 5 Supported by the key 9 and the cam cylinder 5, The first group frame 4 that is a moving frame that moves forward and backward in the direction, the second group frame 6 that is supported by the cam cylinder 5 and moves forward and backward in the optical axis direction, the shutter frame 7 that is held by the second group frame 6 and moves forward and backward, and the liquid crystal The first lens group 51 and the third lens group 23 held by the fixed support 12 and the first lens group held by the first lens frame 4 as a photographing lens group arranged in order from the front of the lens barrel to the rear of the imaging element 14 21, a liquid crystal lens group 22 as a second group lens held by the liquid crystal lens unit 51, and a third group lens 23 held by the third group frame 8.

  In addition to the lens barrel 1, the digital camera 131 in which the lens barrel 1 is incorporated includes a liquid crystal display unit 134, a camera exterior front cover unit 135 including a power supply unit, as shown in FIG. 6. A camera exterior rear cover unit 136 is arranged.

  The rectilinear frame 3 is driven to advance and retreat in an integrated state with the cam cylinder 5 in the optical axis direction in a state in which the rotation is restricted via a guide protrusion 3 a fitted into the rectilinear groove 2 b of the fixed frame 2.

  The cam cylinder 5 is a cylindrical frame member, and a rear end portion thereof is fitted into the inner periphery of the fixed frame 2 and is supported so as to be able to rotate and advance / retreat. The cam cylinder 5 includes a helicoid screw (male) 5a that engages with a helicoid screw (female) 2a of the fixed frame 2, three cam grooves 5c that are provided on the outer peripheral surface 5e and that are spaced 120 ° apart, and , And three cam grooves 5d provided on the inner peripheral surface. The cam groove 5d is rotated by a zoom drive motor (not shown) via a zoom drive gear (not shown). At the same time, the helicoid screw 2a provided on the fixed frame 2 moves forward and backward in the optical axis direction.

  The first group frame 4 is a cylindrical frame member that holds the first group lens 21, and is fitted between the rectilinear frame 3 and the cam cylinder 5 and is projected into a rectilinear groove 2 b of the fixed frame 2 (described later). The outer diameter of the cam follower shaft insertion hole is supported in a state where the rotation is restricted. Three cam followers 31 that engage with the cam groove 5c of the cam cylinder 5 are provided at three divided positions of the inner peripheral surface 4b of the group frame 4, and the cam groove 5 causes the cam groove 5 to move forward and backward. It is driven back and forth in the optical axis direction through the cam follower. In addition, a front face of the first group frame 4 is fixed to a front face of the first group lens 21 and has a decorative plate 11 having an opening, and a lens barrier capable of opening and closing the opening inside the decorative board 11. 25 is arranged.

  The second group frame 6 is a cylindrical frame member that holds the shutter frame 7 and the liquid crystal lens unit 51. The second group frame 6 is fitted into the inner peripheral portion of the cam cylinder 5 and is supported in a state where its rotation is restricted by the float key 9. Three cam followers 32 that engage with the cam grooves 5d of the cam cylinder 5 are provided at three divided positions on the outer peripheral surface of the second group frame 6, and the second group frame 6 is moved forward and backward by the cam cylinder 5. Thus, the cam groove moves forward and backward in the optical axis direction via the cam follower.

  The shutter frame 7 includes a shutter blade 24 that moves forward and backward in the optical axis direction together with the second group frame 6 and is driven to open and close on the front side.

  The fixed support 12 holds the optical filter 15 and the third group lens 23. In order to prevent dust from accumulating on the protective plate of the image sensor between the optical filter 15 and the image sensor 14, a packing material 8 having a circular shape or a rectangular cross section of silicon rubber or urethane rubber material filled with carbon. Are bonded to the optical filter 15. When the image sensor 14 is orthogonal in the plane, the protection plate of the image sensor slides on the packing material.

  The liquid crystal lens unit 51 is a lens unit incorporating a liquid crystal lens group 22 having variable lens power (variable focal length) as shown in the sectional view of FIG. 3 and the exploded perspective view of FIG. Front and rear outer frames 52 and 53 that are fixedly supported to the inner frame, an intermediate frame 54 that is a lens frame member that fits into the inner peripheral recess 52a of the front outer frame 52, and an inner peripheral recess of the rear outer frame 53 A holding frame 55 which is a lens frame member fitted into 53a, a heat conduction coil 66 having high heat conductivity wound around the outer periphery of the middle frame 54, and a heat insulating member covering the outer periphery of the wound heat conduction coil 66 And the liquid crystal lens group 22 that is fitted into the inner peripheral portion 54a of the middle frame 54 and inserted into the rear end concave portion 54d.

  The front and rear outer frames 52 and 53 are ring-shaped lens frame members made of a heat insulating member.

  The middle frame 54 is a heat conducting member made of aluminum alloy or graphite and carbon fiber filled PPS (polyphenylene sulfide resin), and has a cylindrical outer periphery with flange portions 54c and 54d formed at the front and rear ends, and an optical axis O. A circular step portion 54i and a circular opening portion 54j are provided in the front end flange portion 54c, and a U-shaped notch-like recess portion is provided in the rear end flange portion 54d. 54f is provided. Further, two positioning projections 54g as positioning means are provided in the vicinity of the back surface of the circular opening 54j of the lower surface portion 54a of the rectangular opening portion, and positioning is performed in the vicinity of the back surface of the circular opening 54j of the left surface portion 54b of the square opening portion. Two positioning projections 54h as means are arranged (FIGS. 3 to 5).

  The holding frame 55 is a heat conductive member made of aluminum alloy or graphite and carbon fiber-filled PPS, and is a ring-shaped member having a central opening 55a. The positioning pin engages with the positioning hole 54e of the middle frame 54. 55e.

  The liquid crystal lens group 22 includes a rectangular plate-like rear transparent plate made of a quadrilateral front transparent electrode plate 56 made of a glass substrate provided with a common electrode 57 on the inner surface side and a glass substrate made of a pattern electrode 60 provided on the inner surface side. A liquid crystal lens unit enclosed between the alignment films 58 and 59, the electrode plate 61, the front and rear transparent electrode plates 56 and 61 facing each other, and having quadrilateral alignment films 58 and 59 disposed at a predetermined interval. The four-sided nematic liquid crystal layer 62 and the seal 65 for enclosing the liquid crystal layer 62 are included.

  These constituent members are integrated by bonding or the like, and form a liquid crystal lens group 22 having a quadrangular prism shape from which the upper end portion of the rear transparent electrode plate 61 protrudes.

  The pattern electrode 60 disposed on the rear transparent electrode plate 61 is formed of a transparent electrode plate, and is disposed so as to overlap the central lens portion of the liquid crystal lens group 22. A plurality of concentric circular electrodes are formed on the circular center electrode and its outer peripheral portion. The C-shaped annular electrode. The center electrode, the innermost-side annular electrode, and the annular electrodes are connected to each other via an annular connecting portion. The center electrode and the annular zone connecting portion are drawn outward and are formed on a part of a connection pattern 61a disposed on one end portion of the rear transparent electrode plate 61 protruding outward of the liquid crystal lens unit 51 as will be described later. It is connected. A common electrode 57 made of a transparent electrode plate disposed on the front transparent electrode plate 56 is also connected to another part of the connection pattern 61 a disposed on one end of the rear transparent electrode plate 61.

  The liquid crystal lens group 22 is inserted into the middle frame 54, the front surface of the front transparent electrode plate 56 is brought into contact with the back surface of the circular opening 54 j of the middle frame 54, and the lower surface (reference surface) of the front transparent electrode plate 56. Is held in a state in which the left surface (reference surface) is in contact with the positioning projection 54h and fixed with an adhesive 54k. In this state, the upper end portion including the connection pattern 61a portion of the rear transparent electrode plate 61 is inserted through the concave portion 54f of the middle frame 54 and exposed to the outside.

  Subsequently, the presser frame 55 is applied from the rear end surface side of the rear transparent electrode plate 61 of the middle frame 54, the presser frame 55 positioning pins 55e are engaged with the positioning holes 54e of the middle frame 54, and are relatively positioned and joined. Fix it. Further, a front convex lens 63 is inserted into the circular stepped portion 54i of the front end flange portion 54c of the middle frame 54 and bonded and fixed. Further, the rear convex lens 64 is bonded and fixed to the back surface side of the opening 55 a of the pressing frame 55.

  Thereafter, the flange portion 54b and the holding frame 55 of the middle frame 54 are fitted into the inner peripheral recesses 52a and 53a of the front and rear outer frames 52 and 53, respectively, and in the assembled state, each member is bonded to the liquid crystal lens unit 51 by bonding. Integrated. In this integrated state, the liquid crystal lens group 22 is coaxial with the front and rear outer frames 52 and 53 via the middle frame 54 and the holding frame 55, that is, the optical axis of the liquid crystal lens group 22 and the front and outer frames 52. , 53 are kept in alignment with the central axis. In addition, a heat conduction coil 66 made of a metal wire plated with gold or copper is wound on the surface of the metal wire on the concave portion formed on the outer peripheral portion of the inner frame 54 with a single wire or a double wire. The outer periphery of the wound and wound heat conduction coil 66 is covered with a heat insulating sheet 67.

  In the assembled liquid crystal lens unit 51, one end portion of the rear transparent electrode plate 61 protrudes from the outer periphery of the liquid crystal lens unit 51, and the connection pattern 61a arranged at the one end portion has a connection FPC (flexible FPC). Printed circuit board) 68 is connected. An end portion of the heat conducting coil 66 also protrudes from the outer periphery of the liquid crystal lens unit 51, and a flexible metal wire or metal foil 69 made of a flat plate-like heat conducting member having flexibility is thermally insulated from the end portion. They are connected in a state covered with a sheet (not shown). The flexible metal plate 69 may be replaced with a coil spring-like metal wire that can be compressed and extended.

  Note that the liquid crystal lens unit 51 described above has a structure in which the middle frame 54 and the holding frame 55 are separated and combined on a plane orthogonal to the optical axis O. Instead, the middle frame and the holding frame It is also possible to adopt a structure in which these are separated and combined vertically or horizontally along a plane parallel to the optical axis O. In this case, it is necessary to wind the heat conducting coil 66 around the outer periphery of the inner frame 54 in the state where the inner frame 54 and the pressing frame 55 are connected to each other in the vertical direction or after the left and right are coupled.

  The liquid crystal lens unit 51 having the above-described configuration is fixedly supported with respect to the second group frame 6 via the front and rear outer frames 52 and 53, and moves forward and backward in the optical axis direction together with the second group frame 6. The connecting FPC 68 and the flexible metal wire or metal foil 69 extending from the outer peripheral portion of the liquid crystal lens unit 51 are folded back in a U shape and formed on the guide protrusion 12a protruding in a direction parallel to the optical axis from the fixed frame support 12. It is supported in a state where a part is fixed. Therefore, when the second group frame 6 is moved back and forth in the optical axis direction, the connecting FPC 68 and the flexible metal wire or metal foil 69 are deformed into a U shape, and the second group frame 6 can be moved back and forth.

  The connection FPC 68 supplies a liquid crystal lens drive signal output from a liquid crystal drive circuit mounted on the printed circuit board 36 to the pattern electrode 60. At the time of shooting, when a driving voltage is applied to the pattern electrode 60 based on the driving signal, the distribution of the bending rate of the liquid crystal layer 62 changes depending on the voltage distribution of the center electrode and each annular electrode, and the lens power (focal length) ) Is controlled and a focusing operation is performed. The connection FPC 68 is also provided with a drive signal pattern for the actuator for driving the shutter blades 24 held by the shutter frame 7.

  Further, the flexible metal wire or metal foil 69 is connected to a heat conducting connector 71 on the imaging unit 34 side described later. In a state where the liquid crystal lens group 22 is below a predetermined temperature and the responsiveness of the lens power control is lowered, the heat conducting coil 66 receives heat from the heat radiating portion 38a on the image sensor support plate 37 side through the heat conducting connector 71. The liquid crystal lens group 22 is warmed via the, and the liquid crystal lens group 22 is maintained in a state having a predetermined response.

  Here, the configuration around the imaging unit 34 will be described.

  A printed circuit board 36, which is an image sensor substrate, is fixed to the rear end surface of the fixed frame support 12 with screws. The printed circuit board 36 is provided with an image pickup unit support plate 37 that can move for blur correction on a plane (XY plane) orthogonal to the optical axis O, and an image pickup unit 34 that includes the image pickup device 14 supported by the support plate. Has been. Further, the printed circuit board 36 is provided with an electromagnetic drive mechanism for moving the image sensor support plate 37 along the XY plane orthogonal to the optical axis O during blur correction.

  The electromagnetic drive mechanism returns to the initial position where the center of the photographic lens coincides with the center of the light receiving surface of the image sensor due to magnetic balance at the end of photographing. At this time, it is effective that the small pieces of the magnetic material are arranged not on the X-axis and Y-axis N or S pole magnet boundary portions but on positions (on the printed circuit board) facing the respective magnet center portions. Further, when the drive coil in the Y direction, which is the vertical direction, is cut off, the image sensor support plate 37 may be coupled to the unit side clip. In this way, the clamped state can be maintained during conveyance such as when the user does not use, and even if the user accidentally falls, the image sensor support plate does not collide with the clamp member on the unit side, and the parts are protected. be able to.

  On the printed circuit board 36, system control such as power control of a fuel cell or secondary battery provided on the camera side, strobe light emission control, display control, input operation control, and control of a liquid crystal lens unit, etc. A TG (timing generator) IC chip or AFE (analog front end) IC chip 40 for driving the image sensor 14 at high speed and a liquid crystal driving circuit are mounted.

  The image sensor support plate 37 is made of a heat conducting member, and an exposed portion in which gold or copper plating is applied to a part of the surface of the image sensor support plate 37 to be described later in order to prevent a temperature rise of the image sensor 14 that is driven at high speed. 38 is provided.

  The electromagnetic drive mechanism includes an image sensor support plate 37 that is movably supported facing the printed circuit board 36, and a guide bearing 45 that supports the image sensor support plate 37. Printed on the substrate 36, rectangular X-axis drive and Y-axis drive print coils 41 and 42 are arranged. Hall elements 48 and 49 for X-axis detection and Y-axis detection are embedded inside the magnetic material 47 and the respective drive print coils 41 and 42 so as to straddle the respective drive print coils. Each of these Hall elements 48 and 49 detects the position of the movable image sensor support plate 37.

  The imaging element support plate 37 is provided with a permanent magnet in which the two are coupled opposite to each other with different polarities magnetized in the thick direction. The guide bearing 45 having a retainer and having at least four steel balls is magnetically provided between at least a pair of the first and second permanent magnets of the imaging element support plate 37 and the magnetic material 47 of the printed circuit board 36. A large pressing force (magnetic attractive force) is applied. When this pressing force is applied, the steel ball of the guide bearing 45 is pressed against the image sensor support plate 37 and the printed board 36. As a result, the rattling of the steel balls interposed between the image sensor support plate 37, the printed board 36, and the guide bearing 45 is removed.

  The lead terminal (not shown) of the image sensor 14 is connected to the image sensor connection FPC 35 by soldering. Further, the terminals of the FPC 35 are connected to the printed circuit board 36 by a connector (not shown).

  On the image sensor support plate 37, a first permanent magnet (not shown) magnetized in the thick direction at a position facing the X-axis driving print coil 41 disposed on the printed circuit board 36 has an N pole. The S pole is polarized and magnetized so that it is aligned in the extending direction of the imaging element connecting FPC 35. The second permanent magnet (not shown) is polarized and magnetized so that the N pole and the S pole are aligned in a direction orthogonal to the extending direction of the FPC 35.

  On the other hand, the Y-axis driving print coil 42 has a horizontally long rectangular shape, and is arranged such that its long side faces each magnetic pole of the first permanent magnet. Similarly, the X-axis drive print coil 41 has a horizontally long rectangular shape, and is arranged so that its long side faces each magnetic pole of the second permanent magnet.

  The CPU 39 that controls the position of the image sensor support plate 37 that supports the image sensor 14 is connected to a drive circuit disposed on the printed circuit board 36, and the image sensor support plate 370 and the heat radiating portion 38 a of the exposed portion 38 are horizontally aligned. The drive circuit for driving a certain movement in the X-axis direction and a movement in the Y-axis direction which is the vertical direction of the image sensor support plate 37 is controlled.

  The CPU 39 performs control to move the image sensor support plate 37 to a desired position based on an angular velocity input from a gyro (not shown). When the vertical X- and Y-axis drive print coils 41 and 42 are energized in the magnetic flux of the permanent magnets arranged on the image sensor support plate 37 and joined with different polarities, the image sensor support plate 37 moves and the Hall element 48 is moved. 49, position detection is performed. When the X and Y axis drive print coils 41 and 42 are de-energized, the image sensor support plate 37 returns to the initial position due to the magnetic balance between the magnet and the magnetic material.

  When the photographing lens unit vibrates during photographing, the image sensor 14 on the movable image sensor support plate 37 moves in a two-dimensional direction as described above, and the image shake is corrected on the light receiving surface of the image sensor 14. can do.

  The heat dissipating part 38a from which the white paint is peeled off from the exposed part 38 of the image sensor supporting plate 37 has a similar configuration in which the heat radiating part 38a projects from the image sensor supporting plate 37, and engages and disengages from the heat conducting connector 71. A heat dissipating part 38a which is a possible engaging part is provided in an integrated state.

  When the temperature of the image sensor 14 that is driven at high speed increases, the heat generated by the image sensor (heat source) 14 is transmitted to the insulating sheet 43 and the image sensor support plate 37. The heat transfer of the image sensor support plate 37 and the radiation and convection heat of the insulating sheet 43 are transmitted to the heat radiating portion 38 a of the exposed portion 38 held by the support plate 37 and having high heat conduction.

  When the heat dissipating part 38 a of the exposed part 38 is thermally joined to the heat conducting connector 71, it is transmitted to the heat absorbing heat pipes 159 and 160 connected to the heat conducting connector 71. Then, the working fluid takes heat at the wick portion of the heat absorbing portion and evaporates, and the vapor increases the pressure and flows through the vapor passage toward the lower pressure on the heat radiation side, and the heat is released. The condensed working fluid returns to the heat absorbing heat pipes 159 and 160 from the heat pipe (heat radiating portion) again by the wick capillary pump force. The temperature rise of the image sensor 14 can be suppressed by this cycle of evaporation, condensation, and reflux.

  On the other hand, the fixed frame support 12 is provided with a heat conductive connector 71 as a heat radiating plate engaging portion facing the moving direction of the heat radiating portion 38a of the exposed portion 38, and the heat radiating portion 38a can be coupled and detached. ing. When the image sensor 14 is in a non-driven state, the image sensor support plate 37 moves and the heat radiating part 38 a of the exposed part 38 is coupled to the heat conducting connector 71. In the connector connection state, the heat on the image sensor side is transmitted to the heat absorption heat pipes 159 and 160 (FIG. 6) connected to the heat conducting connector 71, from which the liquid crystal display unit 134 and the power supply circuit board 176 of the digital camera described later. It is transmitted to the side heat pipe (heat radiating part). Further, the liquid crystal lens unit 51 is also supplied to the liquid crystal lens group 22 side via a flexible metal wire or metal foil 69 which is a heat conducting member.

  FIG. 6 is a layout view showing a configuration of a main part of a digital camera in which the lens barrel of FIG. 1 is incorporated. 7 is a cross-sectional view taken along the line AA of FIG. 6 and shows a cross section of the heat conducting connector on the lens barrel 1 side.

  In the digital camera 131, in order to suppress the temperature rise of the image pickup device and the IC chip such as the CPU, the heat of the image pickup device 14 which has absorbed heat by the exposed portion 38 which is the core material of the image pickup device support plate 37 on the lens barrel 1 side described above. Is absorbed by the heat absorbing heat pipes 159 and 160 through the heat conductive connector 71 and is radiated to the outside by the heat pipes (heat radiation side) 165 and 166 through the shield plate of the camera exterior body and the liquid crystal display unit. On the other hand, a part of the heat of the image sensor 14 is transferred from the heat conducting connector 71 to the liquid crystal lens group 22 of the lens barrel 1 through the flexible metal wire or the metal foil 69, and the temperature of the liquid crystal lens group 22 decreases. To prevent.

  Specifically, in addition to the lens barrel 1, the digital camera 131 includes a control circuit unit 132, a liquid crystal display unit 134, a camera exterior front cover unit 135 including a power supply unit, and a camera exterior rear cover unit as shown in FIG. 136.

  The heat conducting connector 71 is attached to the inside of the fixed frame support 12 of the lens barrel 1 as shown in FIG. Inside the connector 71, a heat conducting member 74 made of an elastic body is accommodated, and a holding spring 73 having a convex portion 73 a is arranged on the upper part of the connector. The heat conducting member 74 is in contact with the heat absorbing heat pipes 159 and 160 and the flexible metal wire or the metal foil 69 in a state capable of conducting heat.

  During the non-imaging operation period of the image sensor 14, the image sensor support plate 37 is moved and inserted into the heat conduction connector 71 in the heat radiating portion 38 a which is the exposed portion 38 on the image sensor support plate 37 side, and is in a coupled state. In the coupled state, the concave portion 38b of the heat radiating portion 38a is engaged with the convex portion 73a of the holding spring 73, the contact state between the tip portion of the heat radiating portion 38a and the heat conducting member 74 is maintained, and the heat on the heat radiating portion 38a side is maintained. The heat is transferred to the endothermic heat pipes 159 and 160 and the flexible metal wire or metal foil 69 via the heat conducting member 74. In addition, since the position of the image pick-up element support plate 37 is hold | maintained when the convex part 73a of the presser spring 73 engages with the recessed part 38b of the thermal radiation part 38a, it supplies with electricity to the drive print coils 41 and 42 for position maintenance. Is no longer necessary.

  Further, a temperature-sensitive changeover switch 75 is disposed at a connection portion between the heat conducting coil 66 and the flexible metal wire or metal foil 69 wound around the outer periphery of the liquid crystal lens unit 51. This temperature-sensitive changeover switch 75 is a member for switching the contact state made of a shape memory alloy or a heat-sensitive magnetic material, and enters the contact state when the temperature of the liquid crystal lens group 22 falls below an allowable temperature in response. The heat of the flexible metal wire or metal foil 69 is transmitted to the heat conduction coil 66 side. When the temperature exceeds the allowable temperature, the state is switched to a cut state (separated state), and the heat of the flexible metal wire or the metal foil 69 is not transferred to the heat conduction coil 66 side. When the heat conducting coil 66 is composed of a plurality of pieces (multiple winding), the temperature sensitive changeover switch 75 is composed of a plurality of switch groups 76.

  The control circuit unit 132 includes a control circuit board 141 fixedly supported on the camera body, an IC chip 142 such as a CPU, AFEIC, and ASIC mounted on the control circuit board 141, and silicon rubber or the like on the IC chip 142. A pipe joint 145 having a plurality of (three) endothermic heat pipes 144 bonded and fixed via the heat conductive sheet 143, to which end portions of the endothermic heat pipes 159 and 160 are connected, and a control circuit The flexible tubes 159A and 160A connected to the pipe joint 145 on the substrate 141, the tube fixing members 146, 147 and 148 for positioning the flexible tubes 159A and 160A, and the endothermic heat pipe 144 are connected and connected. The flexible tube 161 is provided. The tube fixing members 146, 147, and 148 are provided with positioning pins 146a, 147a, and 148a for the control circuit board 141.

  The endothermic heat pipes 159 and 160 are guided to the control circuit board 141 of the camera control circuit unit 132 along the connection FPC 159 and fixed with the pressing members 145, 146, 147, and 148 and the flexible tubes 159A and 160A and the bellows. They are connected to heat pipes (heat radiation side) 165 and 166 through connecting pipes 162 and 163, respectively.

  The liquid crystal display unit 134 includes an LCD 171 including a backlight, a shield plate 172 that covers the LDC 171, and a heat pipe (heat radiation side) 165. The shield plate 172 is formed of a metal plate and is supported in a thermally coupled state with respect to the camera exterior cover.

  One of the heat pipes (heat dissipating side) 165 is connected to a flexible tube 159A connected to one side of the heat absorbing heat pipe 159 on the heat conducting connector 71 side via a flexible bellows connecting pipe 162, The other is fixed to the outer surface of the shield plate 172 in a thermally coupled state.

  The camera exterior front cover unit 135 including the power supply unit is disposed inside the camera exterior front cover 178, the camera exterior front cover 178, and in contact with the battery box 174. A power supply circuit board 176 to which the power supply battery 173 is connected, a contact piece 175 having high thermal conductivity disposed in contact with the back surface of the power supply circuit board 176, the contact piece 175, and a camera exterior front cover 178 And a spring body 177 made of a metal plate or a wire rod disposed in thermal contact with each other and a heat pipe (heat radiation side) 166.

  One of the heat pipes (heat radiation side) 166 is connected to a flexible tube 160A connected to one side of the heat absorbing heat pipe 160 on the heat conducting connector 71 side via a flexible bellows connection pipe 163, The other is fixed to the contact piece 175 in a thermally coupled state.

  The camera exterior rear cover unit 136 includes a camera exterior rear cover 182 and a contact piece 181 with high thermal conductivity that contacts the camera exterior rear cover 182 in a thermally coupled state via a spring body 183 made of a metal plate or a wire. And a heat pipe (heat radiation side) 167.

  One of the heat pipes (heat radiation side) 167 is connected to the bellows connection pipe 164 to which the flexible tube 161 on the endothermic heat pipe 144 side is connected, and the other is bonded to the contact piece 181 in a thermally coupled state.

  Note that the endothermic heat pipes 159, 160, 161 described above have a container part, a wick part, and a steam passage, and one end part thereof is open, and the opening part thereof is a bellows connection pipe, or , Connected to a flexible tube. When heat is absorbed from the heat source part with these endothermic heat pipes, the working fluid evaporates, and the steam is connected to the heat pipes (heat radiation side) via the vapor passages via bellows connection pipes or flexible tubes, respectively. ).

  On the other hand, the heat dissipating heat pipes 165, 166, and 167 also have a container part, a wick part, and a steam passage in the same manner as the endothermic heat pipe described above, but one end part thereof is opened, and each opening part is connected to a bellows. It is connected to a tube or a flexible tube. In these heat radiating heat pipes, the steam flowing in from each of the heat absorbing heat pipes is condensed into a working fluid by radiating the heat at an external heat radiating portion. The condensed working fluid is recirculated through the wick portion to the heat absorbing heat pipes through the bellows connection pipe or the flexible tube.

  In the digital camera 131 incorporating the lens barrel 1 of the present embodiment having the above-described configuration, zooming during the photographing operation including the live view operation, that is, during the imaging element operation, as shown in FIG. The rectilinear frame 3, the first group frame 4, and the second group frame 6 move to their smooth positions as the cam cylinder 5 rotates. At the time of focusing, when a focusing voltage is applied to the pattern electrode via the connection FPC 68, the lens power of the liquid crystal layer 62 changes and focusing is performed.

  Further, during the imaging element operation period, the imaging element 14, the IC chip 142 such as CPU, AFEIC, ASIC, and the battery box 174 that houses the power source battery 173 are heated by the operating current, and the temperature rises.

  The generated heat in the IC chip 142 is absorbed by the endothermic heat pipe 144 via the heat conductive sheet 143. The working fluid in the wick part evaporates due to the heat of the IC chip absorbed by the endothermic heat pipe 156, and the vapor reaches the heat pipe (heat radiation side) 167 through the flexible tube 161 through the vapor passage. The heat of the steam reaching the heat pipe (heat radiation side) 167 is transmitted from the contact piece 181 to the camera exterior rear cover 182 via the spring body 183, and is radiated to the outside. Condenses into hydraulic fluid. The condensed hydraulic fluid passes through the wick part and is returned again to the endothermic heat pipe 144 side, and an endothermic operation is performed.

  When imaging by the imaging device or imaging device non-operating state after observation by the liquid crystal display unit is finished, the imaging device support plate 37 moves and the heat radiating portion 38a of the exposed portion 38 engages with the heat conducting connector 71. . In the connector engagement state, the heat of the heat radiating portion 38a is absorbed by the heat absorbing heat pipes 159 and 160 through the heat conducting member 74, and the heat is heat pipe (heat radiating side) to which the heat pipe is connected. At 165 and 166, heat is radiated from the camera exterior front cover 178 to the outside via the shield plate 172 of the liquid crystal display unit or the contact piece 175. The image sensor 14 is cooled by this heat radiation action.

  Further, when the liquid crystal lens group 22 is in a state where the temperature is lowered to an allowable temperature or less due to responsiveness, a part of the heat of the heat radiating portion 38a is flexibly transmitted by the heat conductive connector 71 via the heat conductive member 74. It is transmitted to the metal plate 69 and further to the heat conduction coil 66, and the outer peripheral portion of the liquid crystal lens group 22 is heated. Due to the heating, the temperature of the liquid crystal lens group 22 rises, and the lens power control is maintained in a state having a predetermined responsiveness.

  The heat of the LCD 171 itself of the liquid crystal display unit 134 is also radiated to the outside from the shield plate 172, and the heat of the power circuit board 176 including the power supply unit is also radiated to the outside from the camera exterior front cover 178.

  According to the digital camera 131 to which the lens barrel 1 of the present embodiment described above is applied, the configuration is simple, and the heat from each IC chip 142 mounted on the control circuit board is caused by the heat pipe attached to each. The heat of the LCD 171 and the power supply unit is conducted to the shield plate 172 of the liquid crystal display unit and the camera exterior, and can be efficiently radiated from each member to the outside.

  Even if the digital camera 131 has a blur correction function and the image sensor 14 moves on the XY plane orthogonal to the optical axis O during the blur correction operation, the heat conducting connector 71 is used when the image sensor is not in operation. By engaging the heat radiation part 38a of the exposed part 38 on the image sensor support plate 37 side, the heat of the image sensor 14 is efficiently taken into the endothermic heat pipes 159 and 160, and the heat is taken to the heat pipe (heat radiation side) 165. Since it is possible to dissipate heat to the outside by transmitting to 166, deterioration of characteristics due to heat generation of the image sensor 14 can be suppressed. On the other hand, by guiding a part of the heat of the image sensor transmitted by the heat conducting connector 71 to the liquid crystal lens group 22 side, it is possible to suppress a decrease in responsiveness due to a decrease in temperature of the liquid crystal lens group 22.

  Further, since the liquid crystal lens group is employed as the focus lens, the focus lens advance / retreat driving mechanism is not required, the configuration of the lens barrel is simplified, and the lens barrel can be easily assembled.

  In addition, instead of the liquid crystal lens group 22 of the lens barrel 1 described above, oil and electrolyte are filled between the front and rear transparent electrode plates 56 and 61, and the transparent electrode is placed outside the front and rear transparent electrode plates 56 and 61. It is also possible to adjust the focal length by adopting a liquid lens having a configuration in which a voltage is applied to the electrolytic solution to change the shape of the boundary between the electrolytic solution and oil.

  Next, a single-lens reflex camera which is a digital camera according to a second embodiment of the present invention will be described with reference to FIGS.

  FIG. 8 is a diagram showing a main configuration of the single-lens reflex camera of the present embodiment. FIG. 9 is a diagram showing an arrangement of focus detection optical systems incorporated in the camera. FIG. 10 is an enlarged cross-sectional view of a condenser lens unit to which the liquid crystal lens in the focus detection optical system is applied. FIG. 11 is a perspective view of a re-imaging optical system applied to the focus detection optical system.

  As shown in FIG. 8, the single-lens reflex camera 200 according to the present embodiment includes an imaging optical system, a finder optical system, and a focus detection optical system, and further, an LCD display device unique to a digital camera. And a memory device for image recording.

  The imaging optical system includes an imaging lens 202 including a diffractive liquid crystal lens 202b that does not have the convex lenses 63 and 64 shown in FIG. 3 in the optical path order, a half mirror 251, a reflection mirror 253, in the order of the optical paths. And an image sensor 252 provided with an infrared cut filter.

  The taking lens 202 can be attached to and detached from the camera body via a mount. The diffractive liquid crystal lens 202b includes a liquid crystal lens 442 having a first diffraction grating and a liquid crystal lens 444 having a second diffraction grating sandwiching a glass substrate 443, as shown in cross-sectional views of FIGS. And glass substrates 441 and 445 disposed outside the liquid crystal lenses 442 and 444 with diffraction gratings. The refraction operation will be described later.

  The viewfinder optical system includes a screen 255, a penta roof prism 256, and an eyepiece lens 257 that are arranged on a planned image plane equivalent to the image plane of the photographing lens 201 on the optical path in the direction reflected by the half mirror 251. It is configured.

  The half mirror 251 is a quick return mirror that can enter or retract into the optical path in conjunction with a shutter (not shown). When the half mirror 251 is at the optical path entry position, the light beam from the photographing lens 201 is directed to the direction of the finder optical system and the image sensor side. It is comprised so that it may divide into.

  The reflection mirror 253 is configured to be able to enter and retreat into the optical path in conjunction with the half mirror 251, and in the state of entering the optical path, a part of the light flux from the photographing lens 201 is used as a focus detection optical system. When guided and retracted from the optical path together with the half mirror 251, the light flux from the photographing lens 201 is guided to the image sensor 252.

  As shown in FIG. 8, the focus detection optical system includes a condenser lens unit 204 disposed in the vicinity of a planned imaging plane 203 equivalent to the imaging plane of the photographing lens 201, and a camera by bending light from the condenser lens unit 204. Re-imaging optics in which a reflecting mirror 254 for compact storage in the body, an aperture stop group 205 having a pair of aperture stops in the vertical and horizontal directions, and a re-imaging lens group are integrally formed corresponding to the aperture stop 205 The system 206 and the photoelectric conversion element array 207 are configured.

  As shown in FIGS. 8 and 9, the re-imaging optical system 206 includes a pair of re-imaging lenses 206a and 206b and re-imaging lenses 206c and 206d in the vertical and horizontal directions according to the arrangement direction of the photoelectric conversion element array 207, respectively. It consists of and. In FIG. 9, the aperture stop group 205 is omitted. Note that the photoelectric conversion element array 207 shown in FIG. 9 can be replaced with a multipoint focus detection system having a horizontal line sensor and a vertical and horizontal cross sensor detected by a vertical line sensor.

  Further, in the combination of the pair of aperture stops 205 and the corresponding pair of re-imaging lenses 206, the center of each aperture stop 205 and the corresponding re-imaging lens 206 are decentered from the optical axis of the photographing lens 201. . Further, the amount of eccentricity is different for each group (in this embodiment, a combination of a vertical direction and a horizontal direction).

  As shown in FIG. 9, when the focus detection range is widened in the direction of bending the optical path, the space required for bending increases. If the area occupied by the condenser lens unit 204 is thin, it is easy to make a space for arranging the reflection mirror 254. If the space is too tight, unwanted light is likely to enter, which is not preferable.

  As shown in the enlarged sectional view of FIG. 10, the condenser lens unit 204 includes a lens unit having a built-in variable power (variable focal length) liquid crystal lens having the same configuration as the liquid crystal lens unit 51 in the first embodiment. . Specifically, the front and rear outer frames 352 and 353 of the lens frame member fixedly supported by the second group frame 6, the middle frame 354 of the lens frame member fitted in the inner peripheral recess of the front outer frame 352, and the middle frame 354 On the other hand, it is wound around the outer peripheral portion of the holding frame 355 of the lens frame member and the inner frame 354 which are engaged with and joined by the positioning pin hole 354e and the positioning pin 355e and fitted into the inner peripheral recess of the rear outer frame 353. A heat conductive coil 366 made of a heat conductive member, a heat insulating sheet 367 made of a heat insulating member covering the outer peripheral portion of the heat conductive coil 366, and a liquid crystal lens group 322 inserted into the inner peripheral portion and the rear end concave portion of the middle frame 354, Consists of.

  The liquid crystal lens group 322 has the same configuration as the liquid crystal lens group 22 applied to the first embodiment, and includes a front transparent electrode plate 356 made of a quadrilateral glass plate provided with a common electrode 357 on the inner surface side. , A rear transparent electrode plate 361 made of a rectangular flat plate-shaped glass plate provided with a pattern electrode 360 on the inner surface side, and a quadrilateral shape facing the inside of the front and rear transparent electrode plates 356 and 361 and arranged at a predetermined interval Alignment films 358 and 359, a quadrilateral nematic liquid crystal layer 362 constituting a liquid crystal lens portion sealed between the alignment films 358 and 359, a seal 365 for sealing the liquid crystal layer 362, and front and rear transparent electrodes It consists of front and back convex lenses 363 and 364 which are optical members that are closely fixed to the front and rear surfaces of the plates 356 and 361 in the optical axis O direction. These constituent members are integrated by bonding or the like to form a liquid crystal lens group 322 having a quadrangular prism shape and protruding from the upper end of the rear transparent electrode plate 361.

  The liquid crystal lens group 322 is inserted into the middle frame 354, brought into contact with the back surface of the opening 354j of the front transparent electrode plate 356, and the lower surface (reference surface) of the front transparent electrode plate 356 is positioned on the positioning projection 354g of the middle frame 54. Then, the left surface (reference surface) is positioned and adhered and fixed in a state where the left surface (reference surface) is in contact with the positioning protrusion 354h. In this state, the upper end portion including the connection pattern portion of the rear transparent electrode plate 361 is inserted through the U-shaped concave portion of the middle frame 354 and exposed to the outside.

  Subsequently, a pressing frame 355 is applied from the rear end surface side of the rear transparent electrode plate 361 of the middle frame 354, and the positioning pins 355e of the pressing frame 355 are engaged with the positioning holes 354e of the middle frame 354 so as to be relatively positioned and joined. , Fix. Further, a front convex lens 363 is inserted into the circular step 354 i of the front end flange portion 354 c of the middle frame 354 and is fixedly bonded. Further, the rear convex lens 364 is bonded and fixed to the back side of the opening 355a of the pressing frame 355.

  The flange portion of the middle frame 354 and the pressing frame 355 are fitted into the inner peripheral recesses of the front and rear outer frames 352 and 353, respectively. In the assembled state, each member is bonded and fixed, and integrated as a condenser lens unit 51. In this integrated state, the liquid crystal lens group 322 is coaxial with the front and rear outer frames 352 and 353 via the middle frame 354 and the holding frame 355, that is, the optical axis of the liquid crystal lens group 322 and the front and outer frames 352. , 353 are held in a state where they coincide with the central axis. A heat conduction coil 366 made of a single wire, a double wire, or a silver-plated metal wire is wound in a coil shape in the recess formed in the outer peripheral portion of the middle frame 354, and the wound heat The outer periphery of the conductive coil 366 is covered with a heat insulating sheet 367.

  The heat conduction coil 366 is thermally connected to the image pickup device 252 via an heat transfer member to an image pickup device support plate (not shown). On the outer peripheral portion of the middle frame 354, the above-described temperature-sensitive changeover switch (not shown) is arranged at a connection site between the heat conduction coil 366 and the heat transfer member. This temperature-sensitive changeover switch is made of a shape memory alloy or a heat-sensitive magnetic material, and is a member for changing the contact state of the heat transfer member. When the temperature of the liquid crystal lens group 322 falls below a temperature allowed for responsiveness, the temperature-sensitive changeover switch enters a contact state, and the heat of the heat conducting member is transmitted to the heat conducting coil 366 side. When the temperature exceeds the allowable temperature, the state is switched to a cut state (separated state), and the heat of the heat conducting member is not transferred to the heat conducting coil 366 side.

  In the assembled condenser lens unit 204, one end portion of the rear transparent electrode plate 361 protrudes from the outer periphery of the condenser lens unit 204, and a connection pattern arranged on the one end portion includes a connection FPC (flexible printed circuit board). ) 368 is connected. Further, the end portion of the heat conducting coil 366 also protrudes from the outer periphery of the condenser lens unit 204, and a flexible plate-like heat conducting member 369 is covered with a heat insulating sheet (not shown) at the end portion. Connected in a connected state. As shown in FIG. 9, the condenser lens unit 204 itself is held in a state of being fixed to the camera body in the vicinity of the planned imaging plane 203 between the reflection mirror 253 and the reflection mirror 254 at the optical path entry position.

  The liquid crystal lens group 322 in the condenser lens unit 204 is controlled to an appropriate focal length state by the drive control voltage applied via the connection FPC 368 based on the focal length information of the mounted imaging lens 201 by the camera control unit. In addition, when the temperature of the liquid crystal lens group 322 is lowered to a state where the predetermined responsiveness cannot be obtained, the temperature-sensitive changeover switch is brought into a contact state, and the liquid crystal lens group 322 is warmed up to the predetermined temperature by the heat conduction coil 366. Therefore, desired responsiveness is ensured. The heat of the image sensor supporting plate that supports the image sensor 252 is transferred to the heat conduction coil 366 through the heat conduction member 369, and the liquid crystal lens group 322 is warmed by the heat.

  Here, the operation of the diffractive liquid crystal lens incorporated in the photographing lens 202 of the single-lens reflex camera 200 of this embodiment will be described with reference to FIG.

  FIG. 12 is a cross-sectional view of the liquid crystal lens showing the operation principle of the diffractive liquid crystal lens incorporated in the photographing lens of the single-lens reflex camera. FIG. 12A shows an AC voltage applied to the liquid crystal lens. FIG. 12B shows a state in which an AC voltage is applied to the liquid crystal lens.

  The first and second liquid crystal lenses 442 and 443 constituting the diffractive liquid crystal lens 202b have the liquid crystal light distribution directions orthogonal to each other. In a state where an AC voltage is not applied to the liquid crystal lens in FIG. 12A, the liquid crystal acts as an ordinary refractive index regardless of the polarization direction of the incident light beam. Since the refractive index of the substrate is equal to the ordinary light refractive index of the liquid crystal, the liquid crystal lens has a function of not deflecting regardless of the polarization direction of the incident light beam.

  Also, as shown in FIG. 12B, when an AC voltage is applied to the first liquid crystal lens 442, the first liquid crystal lens 142 acts as an extraordinary refractive index for P-polarized light, and the P-polarized light is diffracted (deflected). ) On the other hand, the first liquid crystal lens 442 acts as an ordinary refractive index with respect to S-polarized light and does not diffract (deflect) S-polarized light. When an AC voltage is applied to the second liquid crystal lens 444, the second liquid crystal lens 444 acts as an extraordinary refractive index for S-polarized light, and the S-polarized light is diffracted (deflected).

The second liquid crystal lens 444 acts as an ordinary refractive index for P-polarized light and does not diffract (deflect). When an AC voltage is applied to the first and second liquid crystal lenses 442 and 444 as described above, the P-polarized light is deflected by the first liquid crystal lens, and the S-polarized light is deflected by the second liquid crystal lens 444.

  In the single-lens reflex camera 200 having the above-described configuration, as described above, the liquid crystal lens group 322 whose focal length is variable by electrical control is applied to the condenser lens unit 204 of the focus detection optical system. Therefore, there is no movement of the lens and no dust is generated. In addition, since the change in NA used for focus detection can be reduced, stable focus detection accuracy can be obtained.

  Note that a liquid lens can be used as the condenser lens 500 instead of the condenser lens 204 to which the liquid crystal lens of the single-lens reflex camera 200 is applied. The condenser lens 500 to which the liquid lens is applied includes an incident-side positive lens 541, a liquid crystal lens (first medium) 542, a liquid lens (second medium) 543, an exit, as shown in the liquid lens enlarged view of FIG. It is composed of a side positive lens 545. The first medium 542 is lower than the second medium 543. When a voltage is applied so that the boundary shape between the first medium 542 and the second medium 543 is convex toward the AF sensor, the condenser lens is in a state indicated by a solid line 24a. When a voltage is applied so that the boundary shape between the first medium 542 and the second medium 543 is convex toward the photographing lens side, the condenser lens becomes a wavy line 24b.

Based on each embodiment mentioned above, the following structures can be proposed. That is,
(Appendix 1)
In the photographing lens unit described above, the lens frame member is provided with a shutter and the shutter driving unit, and the liquid crystal driving circuit is connected to the transparent electrode plate via a flexible printed circuit board. A photographing lens unit, wherein the flexible printed circuit board is provided with a shutter drive signal pattern for driving the shutter drive unit.

(Appendix 2)
The imaging lens unit described above includes an imaging element support plate having the imaging element and a heat radiating member, and the imaging element is connected to the unit frame member via a flexible printed circuit board and extends in a direction perpendicular to the optical axis. An imaging lens unit, wherein an imaging element support plate is movably supported so as to be orthogonal to the optical axis of the imaging lens by a driving element such as electromagnetic driving or bending ultrasonic driving.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention at the stage of implementation. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  The imaging lens unit of the present invention can keep the temperature of the liquid crystal lens applied to the photographic lens, and can more precisely match the optical axis of the liquid crystal lens arranged on the incident side or the emission side. It can be used as a simple photographic lens unit.

It is a longitudinal cross-sectional view on the optical axis in the retracted state of the lens barrel which is a photographic lens unit of the first embodiment of the present invention. It is a longitudinal cross-sectional view on the optical axis in the imaging | photography possible state of the lens barrel of FIG. It is sectional drawing of the liquid crystal lens unit applied to the lens-barrel of FIG. FIG. 4 is an exploded perspective view of the liquid crystal lens unit of FIG. 3. It is the figure which looked at the state which inserted the liquid crystal lens in the middle frame in the liquid crystal lens unit of FIG. 3 from the back side. FIG. 2 is a layout diagram illustrating a configuration of a main part of a digital camera in which the lens barrel of FIG. 1 is incorporated. It is AA sectional drawing of FIG. 6, Comprising: The cross section of the heat conductive connector by the side of a lens-barrel is shown. It is a figure which shows the main structures of the single-lens reflex camera of 2nd embodiment of this invention. It is a figure which shows arrangement | positioning of the focus detection optical system integrated in the camera of FIG. FIG. 10 is an enlarged cross-sectional view of a condenser lens unit to which a liquid crystal lens is applied in the focus detection optical system of FIG. 9. It is a perspective view of the re-imaging optical system applied to the focus detection optical system of FIG. FIG. 12A is a cross-sectional view illustrating an operation state of the diffractive liquid crystal lens when the diffractive liquid crystal lens is applied to the photographing lens of the single-lens reflex camera in FIG. 8, and FIG. FIG. 12B shows a state in which a voltage is applied to the liquid crystal lens. 1 is a cross-sectional view of a liquid lens that can be applied in place of a liquid crystal lens of a condenser lens of a single-lens reflex camera.

Explanation of symbols

12: Fixed frame support (unit frame member)
14 ... Image sensor 36 ... Printed circuit board (image sensor board)
37: Image sensor support plate 38: Exposed portion (part of the image sensor support plate)
38a ... Radiation part (engagement part)
54, 354 ... Middle frame (mirror frame member)
54f ... concave portion 54g, 54h ... positioning protrusion (positioning means)
56, 356 ... front transparent electrode plate (transparent electrode plate)
61,361 ... rear transparent electrode plate (transparent electrode plate)
63,363 ... front convex lens (optical member)
64, 364 ... Back convex lens (optical member)
66,366 ... heat conduction coil 67,367 ... heat insulation sheet (heat insulation member)
71 ... Heat transfer connector (heat sink engaging part)
134 ... Liquid crystal display unit

Claims (7)

A photographic lens including a liquid crystal lens with a plurality of transparent electrode plates;
A lens frame member for holding the liquid crystal lens inside;
A heat insulating member covering the outer periphery of the lens barrel member;
In the lens frame member, the transparent electrode plate of the liquid crystal lens has an optical axis of the photographing lens and an outer peripheral portion of the transparent electrode plate in a plane orthogonal to the optical axis. A photographic lens unit comprising positioning means for positioning by positioning protrusions provided on the member.   2. The photographic lens unit according to claim 1, wherein the transparent electrode plate is positioned on one outer peripheral portion of the transparent electrode plate by the positioning means.   Furthermore, the image sensor which converts the to-be-photographed image taken in via the said photographic lens into an electrical signal, and the printed circuit board connected to the said image sensor are provided, The said transparent electrode plate is provided on the said printed circuit board. 2. The photographing lens unit according to claim 1, wherein a liquid crystal driving circuit to be connected is mounted.   Further, the image sensor is supported by the unit frame member so as to be movable in a direction perpendicular to the optical axis together with the image sensor while being held by the heat radiating member. 4. The photographing lens unit according to claim 1, further comprising an engaging portion engageable with a heat sink engaging portion connected to a metal wire or an annular plate provided on the frame member. A photographic lens unit according to claim 1;
A liquid crystal display unit;
A digital camera comprising:   The photographing lens unit is replaceable with the digital camera, and the digital camera further includes a focus detection optical system and a finder optical system, and the focus detection optical system includes a liquid crystal lens. 6. The digital camera according to claim 5, further comprising a condenser lens including the lens and a lens frame member that holds the liquid crystal lens therein.   The focus detection optical system includes a heat insulating member interposed between the lens frame member and the camera body, and the transparent electrode substrate of the liquid crystal lens is orthogonal to the optical axis of the condenser lens and the optical axis. 7. The digital camera according to claim 6, wherein the digital camera is positioned through an outer peripheral portion of the transparent electrode plate by positioning means comprising positioning projections provided on the lens frame member with respect to the lens frame member in a plane to be moved. .

Images