JP2018180370A - Lens holding member and image projection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens holding member capable of realizing fine adjustment after lens assembly while reducing the number of components.SOLUTION: A lens holding member 1 includes: a first rotary member 11 being cylindrical and configured to hold a lens 15 and rotate centering the lens 15; a second rotary member 12 configured to rotate independently from the first rotary member 11; and a holding part 13 rotatably holding the second rotary member with regard to a lens-barrel, centering a central axis of the lens. The second rotary member 12 includes a first face 121a facing an inner peripheral surface of the first rotary member 11, and a second face 121b being a surface on the holding part 13 side. The first face 121a and the second face 121b are formed in an eccentric manner.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a lens holding member and an image projection apparatus.

  In an optical apparatus such as an image projection apparatus using a lens unit represented by a camera or a projector, a mechanism for finely adjusting a lens position when assembling the lens to a lens barrel is known (for example, Patent Document 1) Etc.).

  As a mechanism for performing such fine adjustment, although the structure pressed by pressing members, such as a spring and a screw, is mentioned, there existed a problem that a number of parts increased.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a lens holding member that enables fine adjustment after assembling of a lens while suppressing the number of parts.

  In order to solve the problems described above, the lens holding member according to the present invention holds a lens, and rotates independently of a cylindrical first rotating member that rotates around a central axis of the lens and the first rotating member. A second rotation member, and a holding portion rotatably holding the second rotation member with respect to the lens barrel with respect to the central axis of the lens, the second rotation member being the first rotation member. It has a first surface opposite to the inner peripheral surface of the rotating member and a second surface which is a surface on the side of the holding portion, and the first surface and the second surface are formed eccentrically. Ru.

  According to the present invention, it is possible to make fine adjustments after assembling the lens while suppressing the number of parts.

It is a figure showing an example of composition of an image projection device in an embodiment of the present invention. It is a figure showing an example of composition of a lens barrel in an embodiment of the present invention. It is a figure which shows an example of a structure of the lens holding member shown in FIG. It is an exploded view which shows an example of a structure of each part of the lens holding part shown in FIG. It is a schematic diagram which shows an example of rotation operation of the 2nd rotation member shown in FIG. FIG. 6 is a schematic view illustrating the operation of the shift direction restricting member shown in FIG. 3; It is a figure which shows the state which performs position adjustment of the lens-barrel shown in FIG. It is a figure which shows the structural example of the jig shown in FIG. It is a figure which shows typically position adjustment by the jig shown in FIG. It is a figure which shows typically position adjustment by the jig shown in FIG.

As an embodiment of the present invention, an example of the configuration of an image projection apparatus is shown in FIG.
The image projection apparatus 100 has a light source 101 for emitting a light flux, and a spatial light modulation element 102 for displaying an image to be projected and providing image information to the light flux to be transmitted.
The image projection apparatus 100 also includes a lens unit 200 as a projection optical system for projecting an image on the display surface 104 and a control unit 109 that controls the spatial light modulation element 102 to display an image to be projected on the display surface 104. And.

The light source 101 emits white light substantially in parallel by using a halogen lamp which is a light emission source for emitting a light beam. Here, as a light source, a metal halide lamp, a high pressure mercury lamp, or an LED may be used.
The light source 101 is a white light source, but a plurality of single color light sources such as laser light sources corresponding to basic colors such as R, G and B may be used.

  The spatial light modulation element 102 is a liquid crystal panel which is an image display means for giving image information by transmitting the incident light flux, applying spatial modulation and emitting the light. The spatial light modulator 102 may be a reflective spatial light modulator such as a DMD (digital micro mirror device).

The configuration of the lens unit 200 will be described.
Here, the optical axis of incident light to the lens unit 200 in a state where the lens unit 200 is attached to the image projection apparatus 100, that is, the lens optical axis of the lens optical axis is the Z axis and the direction perpendicular to the Z axis. An axis parallel to Y is defined as Y axis, and an axis perpendicular to Z axis and Y axis is defined as X axis. In each of the directions of the X axis, the Y axis, and the Z axis, the direction of the arrow shown in FIG. 2 is defined as a positive direction.

As shown in FIG. 2, the lens unit 200 includes a housing 20 which is a lens barrel, at least one lens 15 which is disposed on the Z axis to constitute a projection optical system, and a first rotating member 11 which holds the lens 15. And the second rotating member 12 that rotates independently of the first rotating member 11.
The lens unit 200 holds the lens 16 different from the lens 15 and is attached to the housing 20 rotatably around the Z axis, the base member 13, the base member 13 and the second rotation member 12. And a shift direction restricting member 14 disposed between them.

  The first rotating member 11, the second rotating member 12, the base member 13, and the shift direction restricting member 14 are fastened by a pressing member 17 as shown in FIG. 3, and a lens holding device for holding the lens 15 and the lens 16 It functions as the member 1.

The exploded view of each member which comprises the lens holding member 1 in FIG. 4 is shown.
The first rotating member 11 is a cylindrical member that holds the outer edge of the lens 15.
The first rotating member 11 is formed on the inner circumferential side with a groove portion 111 fitted with a convex portion 141 of the shift direction regulating member 14 described later, a fitting portion formed on the outer circumferential side of a cylinder, and the inner circumferential side And a flat portion 113, which is a surface on which at least a portion abuts.
In the present embodiment, the shift direction restricting member 14 protrudes and the first rotating member 11 receives the shape, but the configuration is not limited to this as long as they fit each other, and a convex portion and a concave portion May be reversed.

The second rotating member 12 has a cylindrical portion 121 and a flange portion 122 formed at an end of the cylindrical portion 121 in the Z direction.
The outer peripheral surface 121 a of the cylindrical portion 121 is a first surface facing the first rotating member 11 in a fastening state in which the lens holding member 1 is assembled. Similarly, the inner circumferential surface 121 b of the cylindrical portion 121 is a second surface facing the shift direction restricting member 14.
The outer peripheral surface 121a of the cylindrical portion 121 and the inner peripheral surface 121b are configured in such a manner that the cross section of the XY plane is eccentric as shown in an exaggerated manner in FIG.

For example, as shown in FIGS. 5A to 5C, when the second rotary member 12 is rotated in the A direction, the second rotary member 12 is a shift direction restricting member. Since it is supported from the inner peripheral side at 14, the center O of the inner peripheral surface 121b rotates so as to coincide with the Z axis.
Further, the second rotating member 12 is in contact with the flat surface portion 113 of the inner periphery of the first rotating member 11 on the outer peripheral surface 121 a.

Since the center of the outer peripheral surface 121a of the second rotating member 12 is different from the center of the inner peripheral surface 121b by this configuration, when the first rotating member 11 and the second rotating member 12 are independently rotated, the base The center of the first rotating member 11 is shifted with respect to the center of the member 13.
The flange portion 122 is formed with a corrugated concave portion 122a at a predetermined interval on the outer peripheral side, and the concave portion 122a engages with the jig 70 at the time of the lens fine adjustment described later.

Now, the center position of the lens 15 and the lens 16 slightly differs due to the accumulation of mutual tolerances. Therefore, as shown in FIGS. 6A to 6C, the optical axis center O ′ of the lens 15 attached to the first rotating member 11 and the optical axis center O of the lens 16 attached to the base member 13 It is possible that the shift of the shift from the Y direction which is the shift direction occurs.
At this time, with only the mechanism shown in FIGS. 5A to 5C, as shown in FIGS. 6A to 6C, the optical axis center O 'of the lens 15 is shifted in the shift direction by rotating in the A direction. even moved in, would remain only minute shift amount [Delta] X _2, it is difficult to successfully match the centers of.
Therefore, in the present embodiment, the shift direction restricting member 14 is provided so as to restrict the shift direction of the optical axis center of the lens 15 and to easily determine the shift direction.

The shift direction restricting member 14 is a cylindrical member that is disposed between the second rotating member 12 and the base member 13 and rotates integrally with the first rotating member 11.
The shift direction restricting member 14 includes a first outer peripheral portion 142 which is a surface facing the first rotating member 11 in a fastened state, a second outer peripheral portion 143 which is a surface contacting the second rotating member 12, and an outer peripheral portion 142. And a convex portion 141 formed in a projecting manner.
The shift direction restricting member 14 rotates integrally with the first rotating member 11 when the convex portion 141 engages with the groove portion 111 in the fastened state.
Since the shift direction restricting member 14 rotates independently with respect to the base member 13 and the second rotating member 12, the shift direction restricting member 14 restricts the shift direction of the eccentric second rotating member 12 and the first rotating member 11. It has a function as an eccentric direction restricting member.

By using such a shift direction restricting member 14, as shown in FIGS. 6 (d) to 6 (f), the convex portion 141 fits into the first rotating member 11, and therefore, when the second rotating member 12 rotates. The rotation of the lens 15 and the first rotation member 11 is suppressed.
In other words, the movement of the center O ′ is restricted in the direction coincident with the line connecting the convex portions 141 (particularly in the Y ′ direction in FIGS. 6 d to f) in the XY cross section. At this time, it is desirable that the dimension between the facing flat portions 113 of the first rotating member 11 in the Y ′ direction be equal to the diameter of the outer peripheral surface 121 a of the second rotating member 12.

The base member 13 is a base that holds the lens 16 and is attached to the housing 20 and holds the shift direction restricting member 14, the second rotating member 12, and the first rotating member 11.
The base member 13 functions as a holding portion that holds the second rotating member 12 rotatably with respect to the housing 20 about a Z axis which is a central axis of the lens.
The pressing member 17 is a stopper that is attached to the base member 13 and holds the base member 13, the shift direction regulating member 14, the first rotating member 11, and the second rotating member 12 in a fastened state by pressing the same. .

A method of projecting an image using the lens unit 200 having such a configuration will be described.
The light beam emitted from the light source 101 is given image information by transmitting through the spatial light modulation element 102 disposed on the -Z direction side of the lens unit 200, and transmits through the lens unit 200 to the display surface 104. Be done.
In order for the lens unit 200 to correctly display an image on the display surface 104, it is necessary to adjust the positional relationship with the display surface 104 and the positional relationship with the spatial light modulation element 102.
For such adjustment, there is conventionally known a method of pressing the lens holding member 1 in a desired direction using, for example, a spring or a screw.
However, in the method using the pressing member as described above, there is a problem that the number of parts is increased. Furthermore, in consideration of work efficiency, it is preferable to adjust the position of the lens in a state where the lens holding member 1 is attached to the lens unit 200. In such a configuration, a direction orthogonal to the central axis of the lens, for example, X direction or Y There is also a problem that work from the direction is required and a large work space is required.

Therefore, in the present embodiment, the positional relationship between the lens 15 and the lens 16 can be adjusted by rotating the first rotating member 11 and the second rotating member 12.
An operation of adjusting the positions of the lens 15 and the lens 16 on the Z axis by using the housing 20 and the lens unit 200 configured as described above will be described.

First, in a state where the lens 15 and the lens 16 are attached, the lens holding member 1 is brought into a fastened state.
At this time, as shown in FIGS. 7 and 8, two jigs 70 and 80 which can be inserted into and removed from the lens unit 200 are inserted from the −Z-axis direction side.
Jig 70 is smaller than the inner diameter _{r 200b} of the opening of the -Z direction of the outer diameter _{r 70a} is a lens unit 200, the cylindrical portion 71 larger than the outer diameter _{r 11a} of inner diameter _{r 70b} is the first rotating member 11, the flange The holding portion 72 in the shape of a stick is integrally formed. At the tip of the jig 70 on the insertion direction side, there is provided a projection 73 which engages with the recess 122 a formed in the flange 122 of the second rotating member 12.

The jig 80 has a shape similar to that of the jig 70, and includes a cylindrical portion 81, a grip portion 82, and a projection 83. The outer diameter r _80a is smaller than the inner diameter r _{70b of the} jig 70. larger than the outer diameter _{r 11a} of the rotating member 11. With this configuration, the jig 70 and the jig 80 can be inserted simultaneously, and the efficiency of the position adjustment operation can be improved.

The jig 70 and the jig 80 are both inserted from the -Z direction side of the lens unit 200 as shown in FIGS. 7 and 8, and the projection 73 abuts on the flange portion 122 of the second rotation member 12 to thereby project the projection Reference numeral 83 abuts on the first rotating member 11.
By rotating the jig 70 and the jig 80, it is possible to independently rotate the second rotating member 12 and the first rotating member 11, respectively.

As described above, when the first rotating member 11 and the second rotating member 12 are rotated about the Z axis using the jig 70 and the jig 80, as described in FIGS. In accordance with the rotation angle θ with respect to the one rotation member 11, the center position O of the first rotation member 11 changes by the shift amount ΔX.
The shift amount ΔX may be appropriately set in accordance with the optical design of the lens unit 200. In the present embodiment, the purpose is to eliminate the buildup tolerance of the lens unit 200, and it is sufficient if a shift amount of about 0.1 mm to 0.2 mm is secured, but it is limited to such numerical values. is not.
With this configuration, position adjustment on the XY plane between the lens 16 held by the base member 13 and the lens 15 held by the first rotating member 11 can be performed.
Furthermore, by using the jig 70 and the jig 80, such position adjustment can be performed from the -Z direction side, so that it is possible to prevent a decrease in work efficiency even in a narrow work space.
The lens holding member 1 of the present embodiment is most preferably used to adjust the position of the lens 15 closest to the image plane of the lens unit 200 as described above.

Since the direction in which the lens 15 shifts due to the rotation of the second rotating member 12 and the shift amount ΔX are determined by the eccentric direction of the second rotating member 12, it can be located at any position simply by using the second rotating member 12. Shifting the lens 15 may be difficult.
Therefore, in the present embodiment, the shift direction restricting member 14 that rotates integrally with the first rotating member 11 is disposed between the second rotating member 12 and the base member 13.
With such a configuration, as described with reference to FIGS. 6D to 6F, when the second rotation member 12 eccentrically rotates, the direction itself serving as a reference is rotated relative to the base member 13. And

Specifically, for example, when the direction of the convex portion 141 is parallel to the Y axis, as shown in FIG. 9, the Y axis is set at 0 °, and the rotation angles of the first rotating member 11 and the second rotating member 12 Define θ.
That is, the angle obtained by turning the jig 70 in the A direction with respect to the position of the jig 80 is the rotation angle θ.
The shift amount ΔX is determined according to the magnitude of the rotation angle θ, and the center position O ′ moves on the Y axis when the rotation angle θ changes.
As shown in FIG. 10, when the first rotary member 11 is rotated by the rotation angle θ ₀ using the jig 80, the center position O on the Y ′ axis obtained by rotating the Y axis by the rotation angle θ ₀ is It will move. Rotation angle theta ₀ here is the phase angle of rotation between the second rotating member 12 and the convex portion 141.
With this configuration, the shift direction can be rotated based on the position of the convex portion 141, so that the shift direction and the shift position can be more easily adjusted.
The concave portion 122a has a wave shape periodically formed in accordance with the phase angle, and when it is desired to obtain a predetermined phase angle of rotation by rotating the jig 70 in accordance with the concave portion 122a. Can be easily adjusted.

In the present embodiment, the lens holding member 1 holds the lens 15, and the cylindrical first rotating member 11 rotating about the lens 15 and the second rotating member 12 rotating independently of the first rotating member 11 And a base member 13 which holds the second rotation member 12 and is rotatably attached to the housing 20 about the Z axis.
Further, the second rotating member 12 has an outer peripheral surface 121 a which is a first surface facing the inner peripheral surface of the first rotating member 11, and an inner peripheral surface 121 b which is a second surface facing the shift direction restricting member 14. The inner circumferential surface 121b and the outer circumferential surface 121a are formed eccentrically.
With this configuration, it is possible to make fine adjustments after assembling the lens while suppressing the number of parts.

Further, in the present embodiment, the second rotating member 12 has a concave portion 122a which is a fitting portion to be fitted or fitted to the jig 70 which can be inserted and removed from the direction parallel to the Z axis.
With this configuration, fine adjustment after assembling the lens is facilitated even when it is difficult to secure a working space.

Further, in the present embodiment, the shift direction restricting member 14 is provided with the convex portion 141 disposed between the second rotating member 12 and the base member 13 and fitted to the first rotating member 11.
With this configuration, the shift direction can be freely adjusted, so that fine adjustment after assembling the lens can be performed more accurately while suppressing the number of parts.

In the present embodiment, the concave portion 122 a is periodically formed, and the period is formed in a wave shape in accordance with the phase angle θ ₀ of rotation between the second rotary member 12 and the convex portion 141.
With this configuration, it is possible to more easily adjust the shift direction, thereby enabling fine adjustment after assembling the lens with higher precision.

In the present embodiment, the image projection apparatus 100 has a lens unit 200 having the lens holding member 1 and a light emission source 101 for emitting light toward the lens unit 200, and displays the light transmitted through the lens unit 200. Project to the surface 104.
With this configuration, fine adjustment after lens assembly can be easily performed while suppressing an increase in the number of parts.

  Although the preferred embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and the present invention described in the appended claims unless otherwise specified in the above description. Various modifications and changes are possible within the scope of the present invention.

  For example, although the image projection apparatus is a single-plate color projector that provides color image information with one liquid crystal panel, the present invention is not limited to this, and a three-plate color projector may be used. It may be.

  The effects described in the embodiments of the present invention only list the most preferable effects resulting from the present invention, and the effects according to the present invention are limited to those described in the embodiments of the present invention is not.

DESCRIPTION OF SYMBOLS 1 Lens holding member 11 1st rotation member 12 2nd rotation member 13 Support part (base member)
14 Eccentric Direction Control Member (Shift Direction Control Member)
15 and 16 Lens 17 Holding member 20 Housing 100 Image projection device 141 Convex part 122 Fitting part (wave-shaped part)
122a fitting part (concave part)
200 lens barrel (lens unit)
θ phase angle

Patent No. 5350163 Patent No. 3961797 gazette Japanese Patent Laid-Open No. 2002-196206

Claims (5)

A cylindrical first rotating member for holding a lens and rotating about the lens;
A second rotating member that rotates independently of the first rotating member;
And a holding unit configured to rotatably hold the second rotation member with respect to the lens barrel with respect to the central axis of the lens.
The second rotating member has a first surface facing the inner peripheral surface of the first rotating member, and a second surface which is a surface on the holding portion side, and the first surface and the second surface A lens holding member characterized in that it is formed eccentrically with the second surface. In the lens holding member according to claim 1,
A lens holding member characterized in that the second rotating member has a recess fitted with a jig which can be inserted and removed from a direction parallel to the central axis. The lens holding member according to claim 1 or 2
A lens holding member comprising: an eccentric direction restricting member provided with an engaging portion disposed between the second rotating member and the holding portion and fitted to the first rotating member. In the lens holding member according to claim 3,
A lens holding member comprising: a fitting portion formed in accordance with a phase angle of rotation between the second rotation member and the engagement portion. A lens unit comprising the lens holding member according to any one of claims 1 to 4.
A light emitting source for emitting light toward the lens unit;
And projecting the light transmitted through the lens unit onto a display surface.

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