Lens mount mechanism and projection-type image display device provided with same

Abstract

This lens mount mechanism comprises: a mount base that is provided with a mount surface which contacts a lens reference surface of a lens in the extension direction of the optical axis; a cantilevered first elastic member that is provided with a first free end, a first fixed end, and a biasing surface on which an engagement tab of a projection lens slides in the circumferential direction with respect to the optical axis, and that biases the engagement tab via the biasing surface in a direction such that the lens reference surface and the mount surface remain in contact; and a second elastic member that is provided with a second free end and a second fixed end, and that, via the second free end, biases a portion of the first elastic member which is on the back surface on the opposite side from the biasing surface and which is away from the first free end.

Description

Lens mount mechanism and projection-type image display device equipped with the same

[0001] The present disclosure relates to a lens mount mechanism that detachably holds a lens, and a projection-type image display device including the same.

[0002] For example, Patent Document 1 discloses a lens mount mechanism that detachably holds a lens. The lens mount mechanism described in Patent Document 1 is a so-called bayonet-type lens mount mechanism, in which the lens is moved in the direction of extension of its optical axis to be inserted to the innermost part of the lens mount mechanism, and then the lens is rotated around the optical axis, whereby the lens is held by the lens mount mechanism.

[0003] Specifically, the lens mount mechanism described in Patent Document 1 has a cantilevered elastic member (a so-called leaf spring) that biases the lens in the direction of the optical axis. When the lens is rotated, an engagement claw provided on the lens rides on a convex portion provided on the free end of the elastic member. This causes the elastic member to bend and deform so that the free end is displaced. The bent elastic member biases the engagement claw in the direction of the optical axis, thereby maintaining a state in which the lens reference surface of the lens is in contact with the mount surface of the lens mount mechanism. As a result, the lens is held in the lens mount mechanism.

[0004] JP 2022-117430 A

[0005] However, with the lens mount mechanism described in Patent Document 1, it is not easy to achieve both lens retention and lens attachment. Specifically, the elastic member must be carefully designed, taking into account both lens retention and lens attachment. First, considering high lens retention, i.e., to ensure that the lens continues to be securely held in the lens mount mechanism, it is preferable that the elastic member have high rigidity. However, if the elastic member has high rigidity, the lens's engagement claws will have difficulty climbing onto the elastic member (its convex portion) and, even after climbing onto it, will have difficulty sliding on the elastic member. In other words, the elastic member is less likely to bend or deform. Therefore, when attaching a lens to the lens mount mechanism, the user must continue to rotate the lens with a strong force from the beginning. Therefore, if the elastic member has high rigidity, the lens attachment will be less easy.

[0006] Therefore, an object of the present disclosure is to easily achieve both lens holding performance and lens attachment performance in a lens mount mechanism for a projection-type image display device or the like.

[0007] In order to solve the above-mentioned problems, according to one aspect of the present disclosure, there is provided a lens mount mechanism for detachably holding a lens having a lens reference surface and an engagement claw, the lens mount mechanism comprising: a mount base having a mount surface that contacts the lens reference surface in the direction of extension of the optical axis of the lens; a cantilever-shaped first elastic member having a first free end, a first fixed end, and a biasing surface along which the engagement claw slides circumferentially relative to the optical axis, and biasing the engagement claw via the biasing surface in a direction in which the lens reference surface and the mount surface remain in contact; and a second elastic member having a second free end and a second fixed end, and biasing via the second free end a portion of the back surface of the first elastic member that is away from the first free end, on the opposite side to the biasing surface.

[0008] According to another aspect of the present disclosure, there is provided a projection-type image display device including the above-described lens mount mechanism.

[0009] According to the present disclosure, in a lens mount mechanism for a projection image display device or the like, it is possible to easily achieve both lens holding properties and lens attachment properties.

[0010] 1 is a schematic perspective view of a projection-type image forming apparatus according to an embodiment of the present disclosure; 2 is a front perspective view of a lens holding mechanism holding a projection lens; 3 is a rear perspective view of the lens holding mechanism holding a projection lens; 4 is an exploded perspective view of the lens holding mechanism; 5 is a rear perspective view of the lens mount mechanism; 13C, a schematic diagram for explaining the biasing of the projection lens against the engagement claw by the first and second elastic members, corresponding to FIG. 13D. A schematic diagram showing elastic members in a lens mount mechanism according to another embodiment.

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of well-known matters or redundant explanation of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following explanation and to facilitate understanding by those skilled in the art.

[0012] The inventor(s) provide the accompanying drawings and the following description to enable those skilled in the art to fully understand the present disclosure, and do not intend for them to limit the subject matter described in the claims.

[0013] Hereinafter, an imaging device according to an embodiment of the present disclosure will be described with reference to the drawings.

[0014] Fig. 1 is a schematic perspective view of a projection type image forming apparatus according to an embodiment of the present disclosure. Fig. 2 is a front perspective view of a lens holding mechanism holding a projection lens. Fig. 3 is a rear perspective view of the lens holding mechanism holding a projection lens. Fig. 4 is an exploded perspective view of the lens holding mechanism.

[0015] Note that the X-Y-Z Cartesian coordinate system shown in the figures is intended to facilitate understanding of the embodiments of the present disclosure and does not limit the embodiments of the present disclosure. The X-axis direction is the front-to-rear direction of the projection-type image display device, the Y-axis direction is the left-to-right direction, and the Z-axis direction is the height direction. The optical axis of the projection lens extends in the X-axis direction. Furthermore, in this specification, the image projection direction of the projection-type image display device, i.e., the side of the projection-type image display device where the screen exists, is referred to as the "front side," and the opposite side is referred to as the "rear side."

[0016] 1, a projection-type image display device 10 according to this embodiment has a housing 12 and a projection lens 100 mounted on the housing 12. The projection-type image display device 10 projects an image onto a screen or the like via the projection lens 100.

[0017] 2 and 3, in this embodiment, the projection lens 100 is held by a lens holding mechanism 14 mounted in the housing 12. The lens holding mechanism 14, which will be described in detail later, is configured to hold the projection lens 100 so that the projection lens 100 is detachable and shiftable in directions (Y-axis direction and Z-axis direction) intersecting the extension direction of its optical axis C (X-axis direction).

[0018] 4, the lens holding mechanism 14 has a lens mount mechanism 16 that detachably holds the projection lens 100, and a lens shift mechanism 18 that shifts the lens mount mechanism 16 in directions (Y-axis direction, Z-axis direction) that intersect with the extension direction (X-axis direction) of the optical axis C of the projection lens 100. The lens mount mechanism 16 is fixed to the front end of the lens shift mechanism 18.

[0019] Fig. 5 is a rear perspective view of the lens mount mechanism. Fig. 6 is a rear view of the lens mount mechanism. Fig. 7 is a front view of the lens mount mechanism. Fig. 8 is an exploded perspective view of the lens mount mechanism. Note that some components are omitted from Figs. 5 to 8.

[0020] 5 to 7, the lens mount mechanism 16 has a mount base 20 that contacts and supports the projection lens 100, and first and second elastic members 22, 24 that bias the projection lens 100 to maintain contact between the projection lens 100 and the mount base 20. The lens mount mechanism 16 is attached to the lens shift mechanism 18 via the mount base 20.

[0021] The mount base 20 of the lens mount mechanism 16 has a cylindrical portion 20a into which a portion of the projection lens 100 enters. A plurality of lens support portions 20b are provided at the rear end of the cylindrical portion 20a, protruding toward the central axis of the cylindrical portion 20a (i.e., the optical axis C of the projection lens 100). As shown in FIG. 7 , each of the plurality of lens support portions 20b has an arc shape and is arranged at intervals in the circumferential direction R relative to the optical axis C. Furthermore, each lens support portion 20b has a mount surface MS on its front surface, which comes into contact with the projection lens 100. The mount surface MS is located on the same plane that intersects with the direction in which the optical axis C extends (the Z-axis direction).

[0022] Fig. 9 is a rear perspective view of the projection lens, and Fig. 10 is a rear view of the projection lens.

[0023] 9 and 10 , the projection lens 100 of the projection type image display device 10 according to this embodiment has an annular flange 100a. The flange 100a has a lens reference surface CS on its rear surface. When the projection lens 100 is held by the lens mount mechanism 16, the lens reference surface CS remains in contact with the mount surface MS of the mount base 20 of the lens mount mechanism 16.

[0024] The first and second elastic members 22 and 24 bias the projection lens 100 to maintain contact between the lens reference surface CS of the projection lens 100 and the mount surface MS of the mount base 20 .

[0025] In this embodiment, as shown in FIGS. 5 to 8, the first and second elastic members 22, 24 are cantilevered leaf springs made of a metal material, and extend in the circumferential direction R.

[0026] 8 , the first elastic member 22 has a first free end 22 a and a first fixed end 22 b. The first fixed end 22 b is fixed to the rear end surface 20 c of the cylindrical portion 20 a of the mount base 20 via a fixing screw 26. The second elastic member 24 has a second free end 24 a and a second fixed end 24 b. The second fixed end 24 b is fixed to the rear end surface 20 c of the cylindrical portion 20 a of the mount base 20 via a fixing screw 28.

[0027] In the present embodiment, for reasons that will be described later, the first elastic member 22 has lower rigidity than the second elastic member 24. In other words, the first elastic member 22 is more susceptible to bending deformation than the second elastic member 24. For this reason, the first elastic member 22 has a smaller thickness than the second elastic member 24.

[0028] 6, the first elastic member 22 and the second elastic member 24 partially overlap each other. There are multiple pairs of the first elastic member 22 and the second elastic member 24 that overlap each other, and the multiple pairs are provided at intervals in the circumferential direction R on the rear end surface 20c of the cylindrical portion 20a of the mount base 20.

[0029] 11 is a side view of the first and second elastic members 22, 24. That is, FIG. 11 shows the first and second elastic members 22, 24 as viewed in the radial direction from the optical axis C.

[0030] 11 and 5, the second elastic member 24 is located forward of the first elastic member 22 and partially overlaps the first elastic member 22 when viewed in the extending direction of the optical axis C (X-axis direction). In particular, the second free end 24a of the second elastic member 24 overlaps the first elastic member 22. The reason for this will be described later.

[0031] The first elastic member 22 has a biasing surface 22c between the first free end 22a and the first fixed end 22b for biasing the projection lens 100. Specifically, the biasing surface 22c of the first elastic member 22 extends in the circumferential direction R. As shown in Figures 9 and 10 , this biasing surface 22c comes into contact with the engaging claw 110b of the projection lens 100.

[0032] Specifically, the engagement claws 110b protrude outward from the outer peripheral surface of the projection lens 100. As shown in Fig. 10 , the engagement claws 100b have an arc shape extending in the circumferential direction R when viewed in the extension direction of the optical axis C (X-axis direction). Furthermore, a plurality of engagement claws 100b are provided on the projection lens 100 at intervals in the circumferential direction R.

[0033] FIG. 12 is a partial cross-sectional view of the lens mount mechanism with the projection lens attached.

[0034] 12 , the first elastic member 22 biases the engagement claw 100b of the projection lens 100 in a direction in which the lens reference surface CS and the mount surface MS remain in contact with each other (a biasing force F is generated) via the biasing surface 22c that is in contact with the engagement claw 100b of the projection lens 100 in the extension direction of the optical axis C (the X-axis direction). In the present embodiment, the first elastic member 22 biases the engagement claw 100b rearward so as to draw the projection lens 100 into the lens mount mechanism 16.

[0035] From here, a method of mounting the projection lens 100 to the lens mount mechanism 16, that is, the movement path of the engagement claws 100b of the projection lens 100 until the engagement of the engagement claws 100b with the first elastic member 22 is completed, will be described.

[0036] Fig. 13A is a front perspective view of the lens mount mechanism before the projection lens is inserted. Fig. 13B is a rear perspective view of the lens mount mechanism immediately after the projection lens is inserted. Fig. 13C is a rear perspective view of the lens mount mechanism while the inserted projection lens is rotating. And Fig. 13D is a rear perspective view of the lens mount mechanism after the projection lens has been attached to the lens mount mechanism.

[0037] 13A , the user inserts the rear end of the projection lens 100 into the cylindrical portion 20a of the mount base 20 of the lens mount mechanism 16 in the direction in which the optical axis C extends (the X-axis direction). Specifically, the projection lens 100 is inserted into the lens mount mechanism 16 until the lens reference surface CS provided on the rear surface of the flange 100a of the projection lens 100 comes into contact with the mount surfaces MS provided on the front surfaces of the plurality of lens support portions 20b of the mount base 20. At this time, the plurality of engagement claws 100b of the projection lens 100 pass between the plurality of lens support portions 20b.

[0038] As shown in FIG. 13B , immediately after the multiple engagement claws 100b of the projection lens 100 pass between the multiple lens support portions 20b, the multiple engagement claws 100b are not in contact with the first elastic members 22. When the user rotates the projection lens 100 around the optical axis C, the multiple engagement claws 100b move in the circumferential direction R. As a result, as shown in FIG. 13C , the multiple engagement claws 100b come into contact with the first free ends 22a of the corresponding first elastic members 22. The first elastic members 22 that come into contact with the engagement claws 100b are deflected and deformed so that the first free ends 22a are displaced forward. As a result, the engagement claws 100b ride up onto the urging surfaces 22c of the corresponding first elastic members 22.

[0039] When the user further rotates the projection lens 100, the engagement claws 100b slide in the circumferential direction R on the corresponding urging surfaces 22c of the first elastic members 22, further bending and deforming the first elastic members 22. When the projection lens 100 is rotated to the maximum extent, most of the engagement claws 100b are positioned on the corresponding urging surfaces 22c of the first elastic members 22 in the flexed and deformed state, as shown in Fig. 13D. As a result, as shown in Fig. 12, the first elastic members 22 urge the engagement claws 100b rearward via their urging surfaces 22c, and as a result, the lens reference surface CS of the projection lens 100 continues to contact the mount surface MS of the lens mount mechanism 16.

[0040] In this embodiment, the projection lens 100 can rotate until it engages with a stopper pin provided on the lens mount mechanism 16 .

[0041] FIG. 14 is a front perspective view of the lens mount mechanism.

[0042] As shown in FIG. 14 , the mount base 20 of the lens mount mechanism 16 is provided with a stopper pin 30 that can advance and retreat in the direction of extension of the optical axis C (X-axis direction). The stopper pin 30 is biased so as to protrude from the mount surface MS of the lens support portion 20 b. When the lens reference surface CS of the projection lens 100 contacts the mount surface MS, the stopper pin 30 is pushed by the lens reference surface CS and retracts. In this state, the projection lens 100 rotates about the optical axis C, and when the notch 100 c formed in the flange 100 a shown in FIG. 10 reaches in front of the stopper pin 30, the stopper pin 30 protrudes forward and enters the notch 100 c. As a result, the rotation of the projection lens 100 is limited by the stopper pin 30. When the lens release button 32 provided on the mount base 20 is pressed, the stopper pin 30 that has entered the notch 100 c retracts, allowing the projection lens 100 to rotate.

[0043] As described above, the engaging claws 100b of the projection lens 100 come into contact with the first elastic member 22 and are urged by the first elastic member 22. However, the engaging claws 100b do not come into contact with the second elastic member 24. In other words, the second elastic member 24 urges the projection lens 100 without coming into contact with the projection lens 100. A method for urging the projection lens 100 by the second elastic member 24 will now be described.

[0044] 15A to 15C are schematic diagrams for explaining the biasing of the projection lens against the engagement claw by the first and second elastic members, where Fig. 15A corresponds to Fig. 13B, Fig. 15B corresponds to Fig. 13C, and Fig. 15C corresponds to Fig. 13D.

[0045] 15A and 11 , the second free end 24 a of the second elastic member 24 contacts the back surface 22 d of the first elastic member 22 (the surface opposite to the biasing surface 22 c). Specifically, as shown in FIGS. 15A and 6 , the second free end 24 a of the second elastic member 24 biases a portion of the back surface 22 d of the first elastic member 22 that is distant from the first free end 22 a (a portion close to the first fixed end 22 b). Note that when the first elastic member 22 is in a free state, i.e., when the engaging claw 100 b of the projection lens 100 is not in contact with the first elastic member 22, the second free end 24 a of the second elastic member 24 does not have to contact the first elastic member 22.

[0046] 15B, when the projection lens 100 rotates about the optical axis C, the engaging claws 100b ride on the biasing surface 22c of the first elastic member 22, causing the first elastic member 22 to bend and deform. At this time, the first elastic member 22 is substantially bent and deformed from the portion contacting the second free end 24a of the second elastic member 24 to the first free end 22a.

[0047] When the projection lens 100 rotates further and the engaging claw 100b slides on the biasing surface 22c of the first elastic member 22, the second elastic member 24 also begins to bend and deform due to being pushed by the first elastic member 22 which is being bent and deformed. As a result, the second elastic member 24 begins to bias the first elastic member 22.

[0048] 15C, when the projection lens 100 is rotated to the maximum extent, the second free end 24a of the second elastic member 24 is in indirect contact with the engagement claw 100b via the first elastic member 22. In other words, both the first elastic member 22 and the second elastic member 24 substantially bias the engagement claw 100b.

[0049] With such first and second elastic members 22, 24, the biasing force of the projection lens 100 against the engaging claws 100b increases as the projection lens 100 rotates. Therefore, when rotating and attaching the projection lens 100, the rotational resistance of the projection lens 100 is initially low and increases as the projection lens 100 rotates. As a result, the user can start rotating the projection lens 100 with a small amount of force and finish by applying more force, thereby completing the attachment of the projection lens 100 to the lens mount mechanism 16. Therefore, the attachment of the projection lens 100 is easy.

[0050] Furthermore, when the attachment of the projection lens 100 to the lens mount mechanism 16 is complete, the engaging claws 100b of the projection lens 100 are biased by both the first elastic member 22 and the second elastic member 24. As a result, contact between the lens reference surface CS of the projection lens 100 and the mount surface MS of the lens mount mechanism 16 is reliably maintained. Therefore, the projection lens 100 is highly retainable. In other words, as a result of considering the attachability of the projection lens 100, even if the first elastic member 22 alone cannot ensure the necessary retaining force for the projection lens 100, the second elastic member 24 compensates for the insufficient retaining force, thereby reliably retaining the projection lens 100.

[0051] In the present embodiment, as described above, the first elastic member 22 has lower rigidity than the second elastic member 24. Therefore, when rotating and attaching the projection lens 100, the user can start to rotate the projection lens 100 with less force (compared to when the rigidity of the first and second elastic members 22, 24 is equal). In this case, when the attachment of the projection lens 100 to the lens mount mechanism 16 is complete, most of the biasing force of the projection lens 100 to the engagement claw 100b is provided by the second elastic member 24.

[0052] According to the present embodiment as described above, the lens mount mechanism 16 of the projection type image display device 10 can easily achieve both lens holding properties and lens mounting properties.

[0053] Specifically, the rigidity of the second elastic member 24 is appropriately adjusted to achieve high holding performance of the projection lens 100, and the rigidity of the first elastic member 22 is appropriately adjusted to achieve high attachment performance of the projection lens 100. In other words, since the rigidities of the first and second elastic members 22, 24 can be adjusted independently of each other, it is possible to easily achieve both high lens holding performance and lens attachment performance.

[0054] Although the embodiments of the present disclosure have been described above with reference to the above-mentioned embodiments, the embodiments of the present disclosure are not limited to these.

[0055] For example, in the above-described embodiment, the second elastic member 24 is a cantilevered leaf spring, similar to the first elastic member 22. However, the embodiment of the present disclosure is not limited to this. The second biasing member may be, for example, a coil spring.

[0056] In the above-described embodiment, the first fixed end 22b of the first elastic member 22 is fixed to the mount base 20 of the lens mount mechanism 16. Alternatively, the first fixed end of the first elastic member may be fixed to the second free end of the second elastic member. That is, the first and second elastic members may be integrated into one component.

[0057] FIG. 16 is a schematic diagram showing an elastic member in a lens mount mechanism according to another embodiment.

[0058] 16, in a lens mount mechanism according to another embodiment, there is one elastic member 222 that biases one engagement claw 100b of the projection lens 100. The elastic member 222 is similar to the elastic member 222 in the above-described embodiment, in which the first fixed end 22b of the first elastic member 22 is fixed to the second free end 24a of the second elastic member 24. Therefore, the elastic member 222 biases the engagement claw 100b in the same manner as the first and second elastic members 22, 24.

[0059] Specifically, the elastic member 222 has a free end 222 a, a fixed end 222 b, and a folded portion 222 c therebetween. That is, the elastic member 222 extends from the fixed end 222 b in the circumferential direction R, is folded back at the folded portion 222 c, and then extends in the opposite direction toward the free end 222 a.

[0060] With such an elastic member 222, when the projection lens 100 is rotated about the optical axis C, the engagement claw 100b climbs up onto the elastic member 222 from the free end 222a side. Specifically, the engagement claw 100b climbs up onto the urging surface 222d between the free end 222a and the folded-back portion 222c. As a result, the portion 222e of the elastic member 222 between the free end 222a and the folded-back portion 222c is substantially deflected and deformed.

[0061] When the projection lens 100 is further rotated, i.e., when the engagement claw 100b slides on the biasing surface 222d toward the folded portion 222c, the portion 222f of the elastic member 222 between the fixed end 222b and the folded portion 222c also flexes and deforms. Then, when the projection lens 100 is rotated to the maximum extent, the engagement claw 100b is positioned on the folded portion 222c. As a result, the engagement claw 100b is urged by the urging force generated by the flexing and deformation of the portion 222f between the fixed end 222b and the folded portion 222c. As a result, the projection lens 100 is held by the lens mount mechanism according to another embodiment.

[0062] In the case of the elastic member 222, by appropriately adjusting the length of the portion 222e between the free end 222a and the folded portion 222c and the portion 222f between the fixed end 222b and the folded portion 222c, it is possible to easily achieve both lens holding ability and lens attachment ability.

[0063] That is, the lens mount mechanism according to the embodiment of the present disclosure biases the engagement claws of the lens using a first elastic member and a second elastic member (or an elastic member that integrates these as a single component, as shown in FIG. 16 ), and is configured so that the biasing force on the engagement claws increases as the lens rotates.

[0064] Therefore, the lens mount mechanism according to an embodiment of the present disclosure is, in a broad sense, a lens mount mechanism that detachably holds a lens having a lens reference surface and an engagement claw, and includes: a mount base having a mount surface that contacts the lens reference surface in the direction of extension of the optical axis of the lens; a cantilever-shaped first elastic member that has a first free end, a first fixed end, and a biasing surface along which the engagement claw slides circumferentially relative to the optical axis, and that biases the engagement claw via the biasing surface in the direction in which the lens reference surface and the mount surface remain in contact; and a second elastic member that has a second free end and a second fixed end, and that biases via the second free end a portion of the back surface of the first elastic member that is away from the first free end and is opposite the biasing surface of the first elastic member.

[0065] Finally, the lens mount mechanism according to the above-described embodiment is mounted on a projection-type image display device. However, the embodiments of the present disclosure are not limited to this. The lens mount mechanism may be mounted on, for example, an imaging device.

[0066] As described above, the above-described embodiments have been described as examples of the technology of the present disclosure. For this purpose, drawings and detailed descriptions are provided. Therefore, the components described in the drawings and detailed descriptions may include not only components essential for solving the problem, but also components that are not essential for solving the problem in order to exemplify the above-described technology. Therefore, the fact that these non-essential components are described in the drawings or detailed descriptions should not be interpreted as immediately indicating that these non-essential components are essential.

[0067] Furthermore, since the above-described embodiments are intended to illustrate the technology of the present disclosure, various modifications, substitutions, additions, omissions, etc. may be made within the scope of the claims or their equivalents.

[0068] The present disclosure is applicable to a lens mount mechanism that is mounted on a projection image display device or the like and that detachably holds a projection lens.

Claims

1. A lens mount mechanism for detachably holding a lens having a lens reference surface and an engagement claw, comprising: a mount base having a mount surface that contacts the lens reference surface in the direction of extension of the optical axis of the lens; a cantilever-shaped first elastic member having a first free end, a first fixed end, and an urging surface along which the engagement claw slides in the circumferential direction relative to the optical axis, and urging the engagement claw via the urging surface in the direction in which the lens reference surface and the mount surface remain in contact; and a second elastic member having a second free end and a second fixed end, and urging via the second free end a portion of the back surface of the first elastic member that is away from the first free end on the opposite side to the urging surface.

2. The lens mount mechanism according to claim 1, wherein the first elastic member has lower rigidity than the second elastic member.

3. A lens mount mechanism as described in claim 1, wherein the first elastic member is a cantilevered leaf spring extending in the circumferential direction, the second elastic member is a cantilevered leaf spring extending in the circumferential direction, and the first elastic member and the second elastic member partially overlap in the extending direction.

4. A lens mount mechanism according to claim 1, wherein said first fixed end of said first elastic member is fixed to said second free end of said second elastic member.

5. A projection type image display device comprising the lens mount mechanism according to claim 1.

Images