JP3334035B2 - Light transmission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission device, and more particularly, to an optical transmission device suitable for use in obtaining emitted light having a substantially uniform luminance distribution.

[0002]

2. Description of the Related Art Conventionally, various light transmitting devices for transmitting light by a light guide have been provided. For example, as shown in the perspective view of FIG. 1 and the sectional view of FIG.
Condensed light 2a from a light guide (not shown) is incident on one end surface 1a of the columnar optical member 1 as a light guide, is totally reflected by the outer peripheral surface 1c of the optical member 1, and is substantially uniform from the other end surface 1b. There is a light transmission device that obtains the outgoing light 2b having a high luminance distribution. Such a light transmission device transmits only necessary light to the rear optical member 1 and absorbs and dissipates unnecessary heat rays of unnecessary light. Therefore, a light blocking member (not shown) is provided around the incident side end face 1a of the optical member 1. ). Such a light transmission device,
It is used as part of a lighting device.

[0003] In recent years, there has been an increasing demand for higher luminance of lighting devices. However, if the output of a light source lamp is increased to increase the condensing density in order to meet this demand, the light emitted to a light shielding member is increased. And the amount of heat generated by the light shielding member due to the irradiation light increases. Therefore, simply using a high-power light source lamp with the same configuration as that of the conventional light transmission device would cause the light-shielding member to become extremely hot due to the irradiation light.
(For example, 800 ° C.), it was found that new problems such as being damaged or insufficient heat radiation, resulting in thermal deformation of the device and displacement of the position of the optical member 1 occurred.

[0004]

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a light transmitting device capable of avoiding the adverse effect of heat generated by light from a light source.

[0005]

The present invention provides an optical transmission device having the following configuration in order to solve the above technical problems.

That is, the light transmission device includes a light guide, a light guide holding mechanism, a light blocking member, and a heat insulating member. The light guide emits light incident from one end face from the other end face. The light guide holding mechanism holds the light guide. The light blocking member
The light guide is arranged on the incident side with respect to the light guide, and is coupled to the light guide holding mechanism. The light blocking member has an opening hole facing an incident side end face of the light guide. The heat insulating member is interposed between a joint between the light guide holding mechanism and the light blocking member to prevent heat transfer between the light guide holding mechanism and the light blocking member.

In the above configuration, the light guide may be a bendable one such as an optical fiber or a rigid body such as a transparent glass. When the light from the light source passes through the opening of the light shielding member disposed on the incident side of the light guide holding mechanism, it is incident on one end face of the light guide facing the opening and is emitted from the other end face. When a part of the light from the light source is irradiated to the outside of the opening of the light blocking member,
In the irradiated portion, heat is generated due to light absorption. Most of this heat is radiated from the outer surface of the light-shielding member to the outside of the apparatus, but part of the heat is transmitted to a heat-insulating member interposed between the light-shielding member and the light guide holding mechanism. However, since the heat insulating member transmits no or little heat, no or little heat is transmitted to the light guide mechanism.

Therefore, the light transmission mechanism can avoid the adverse effect of heat generation due to light from the light source.

Preferably, the apparatus further comprises a fine adjustment mechanism for supporting the light guide and the light shielding member so as to be finely adjustable in the optical axis direction and / or in the direction perpendicular to the optical axis.

According to the above configuration, the position of the opening of the light shielding member of the light transmission device can be adjusted with respect to the light source. Therefore, while increasing the amount of light passing through the opening of the light-shielding member as much as possible, reducing the amount of light irradiating around the opening of the light-shielding member as much as possible, the light transmission efficiency is increased, and at the same time, the damage due to heat generation of the light-shielding member is prevented. it can.

Preferably, the heat insulating member has a spring washer shape, one end of which is in contact with the light blocking member, and the other end of which is in contact with the light guide holding mechanism.

In the above configuration, the spring washer shape of the heat insulating member is a shape in which a part of the ring is cut and staggered like a spring washer. In order for the light-shielding member to have one end in contact with the light guide holding mechanism and the other end in contact with the light-shielding member, the light-shielding member needs to be rigid or have a very large spring constant even if it has spring properties. The heat insulating member has a ring-shaped heat transfer path from one end in contact with the light blocking member to the other end in contact with the light guide member. Therefore, the heat insulating effect can be enhanced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical transmission device according to an embodiment of the present invention shown in FIGS. 3 to 6 will be described in detail.

As shown in the perspective view of the main part of FIG. 3 and the sectional view of the main part in the axial direction of FIG. The light-shielding member 30 is fixed to the incident-side end face 24 of the lens barrel 20 by a fixing screw 36.
2, the end face 14 on the incident side of the optical member 12 is exposed.

More specifically, as shown in FIG.
Has a cylindrical peripheral wall 21, and a screw hole 28 penetrating in the radial direction is formed in the vicinity of both ends of the peripheral wall 21. The optical member 12 has a support screw 18 screwed into the screw hole 28.
As a result, the lens barrel 20 is held in a floating state in the hollow hole 22 of the lens barrel 20.

The light shielding member 30 is arranged on the light incident side of the optical member 12. The light-shielding member 30 has a large outer diameter so that the surface area is increased and a sufficient heat radiation effect is obtained. The light shielding member 30 is fixed to the incident side end face 24 of the lens barrel 20 using fixing screws 36 via washers 40 arranged on both sides thereof. The washer 40 has a shape in which a part of the ring is cut and staggered like a spring washer, one end 42 of which is in contact with the light shielding member 30 and the other end 44 thereof.
Contacts the lens barrel 20 and the fixing screw 36. Washer 40
Since the heat transfer path from one end 42 to the other end 44 is long, the amount of heat transfer from the light blocking member 30 to the lens barrel 20 (including the case via the fixing screw 36) can be reduced. Preferably, the washer 40 is made of a member having low thermal conductivity.

In the present embodiment, the opening 32 of the light shielding member 30 is slightly larger than the end face 14 of the optical member 12 on the incident side. However, if all or most of the condensed light 2a from the light source 3 passes inside the opening 32 of the light shielding member 30, the opening 32 of the light shielding member 30
May be the same size as the end surface 14 on the light incident side, or may be smaller.

Further, the light transmission device 10 is provided with a fine adjustment mechanism 11 as described below so that the position of the optical member 12 with respect to the light source 3 can be adjusted.

That is, as shown in the perspective view of FIG. 5 and the cross-sectional view perpendicular to the optical axis direction of FIG. 6, the fine adjustment mechanism 11 includes a first member 50 extending in the vertical direction. The second member 60 extending in the horizontal direction is joined at right angles to each other, and the third member 70 supporting the lens barrel 20 is connected to the second member 60.
Be supported by.

More specifically, the first member 50 has an engaging groove 52 and a through groove 54 formed in a vertical direction. The second member 60 has an engagement protrusion 66 fitted into the engagement groove 52, and is supported by the first member 50 so as to be vertically movable along the engagement groove 62 of the first member 50. On the engagement protrusion 66,
A screw hole 68 is formed. The second member 60 is slightly moved in the vertical direction by a feed mechanism (not shown) and fixed through the through groove 54 of the first member 50 to be screwed into the screw hole 68 of the engagement protrusion 66 of the second member 60. The screw 69 fixes the relative position with respect to the first member 50.

Similarly, the second member 60 has an engaging groove 62 and a through groove 64 formed in the horizontal direction. Third member 7
0 has an engagement projection 76 fitted into the engagement groove 62,
The second member 60 is supported by the second member 60 so as to be movable in the horizontal direction along the engagement groove 62. A screw hole 78 is formed in the engagement protrusion 76. The third member 70 is slightly moved in the horizontal direction by a feed mechanism (not shown),
The relative position with respect to the second member 60 is fixed by a fixing screw 79 which is screwed into the screw hole 78 of the engagement projection 76 of the third member 70 through the through groove 64 of the second member 60. .

Next, the operation of the light transmission device 10 will be described. The condensed light 2 a from the light source lamp 3 is incident on the light transmission device 10. Most of the condensed light 2a is
Through one end surface 14 of the optical member 12
And exits from the other end 16. It is preferable that the condensed light 2a be condensed so as to be incident on the optical member 12 at an incident angle equal to or less than a predetermined angle so that total reflection occurs inside the optical member 12. On the other hand, part of the condensed light 2a is
Perimeter 34 of the opening 32 of
Heat is generated by light absorption. Most of this heat is radiated to the outside from the surface of the light shielding member 30, but part of the heat is transmitted to the lens barrel 20 via the washer 40. However, as described above, since the washer 40 does not easily conduct heat, the amount of heat transferred to the lens barrel 20 is extremely small. Therefore, the lens barrel 20 supporting the optical member 12 and the support screw 1
The thermal deformation of 8 hardly occurs.

Further, the position of the light shielding member 30 is adjusted by the fine adjustment mechanism 11. That is, the position of the light shielding member 30 can be finely adjusted in the vertical and horizontal directions so that all or most of the condensed light 2a passes through the opening 32 of the light shielding member 30. Therefore, the condensed light 2a applied to the periphery 34 of the opening 32 of the light shielding member 30 can be eliminated or reduced, and the heat generation of the light shielding member 30 can be eliminated or minimized.

Therefore, adverse effects due to light from the light source,
For example, the light shielding member 30 may be damaged due to heat generation, or the lens barrel 20 may be damaged.
Displacement of the optical member 12 due to thermal deformation of the support screw 14 and the like can be avoided.

The present invention is not limited to the above embodiments, but can be implemented in various other modes.
For example, the optical member may have a columnar shape, a triangular prism shape, a polygonal prism shape of 5 or more, and a method of supporting the optical member is arbitrary.

[Brief description of the drawings]

FIG. 1 is a perspective view of an optical member of a conventional light transmission device.

FIG. 2 is a cross-sectional view of the optical member of FIG.

FIG. 3 is an overall perspective view of the light transmission device according to the embodiment of the present invention.

4 is a sectional view in the optical axis direction of the device of FIG.

FIG. 5 is an overall perspective view when a fine adjustment mechanism is further provided.

FIG. 6 is a cross-sectional view in the direction perpendicular to the optical axis in the case of FIG.

[Explanation of symbols]

 Reference Signs List 10 light transmission device 11 fine adjustment mechanism 12 optical member (light guide) 14a, 14b end surface 16 peripheral surface 18 support screw 20 lens barrel (light guide holding mechanism) 21 peripheral wall 22 hollow hole 24 end surface 28 screw hole 30 light blocking member 32 opening hole 33 around opening 36 fixing screw 40 washer (heat insulating member) 42 one end 44 other end 50 first member 52 engaging groove 54 through groove 60 second member 62 engaging groove 64 through groove 66 engaging protrusion 68 screw hole 69 fixing screw 70 Third member 76 Engagement projection 78 Screw hole 79 Fixing screw

Claims (3)

(57) [Claims] 1. A light guide for emitting light incident from one end face from the other end face, a light guide holding mechanism for holding the light guide, and a light guide holding mechanism disposed on an incident side of the light guide. A light shielding member coupled to a mechanism and having an opening hole facing the incident side end face of the light guide; and a light shielding member interposed between a coupling portion of the light guide holding mechanism and the light shielding member, and A light-insulating member for preventing heat transfer between the light-shielding member and the light-shielding member. 2. A fine adjustment mechanism which supports the light guide and the light shielding member so as to be finely adjustable in an optical axis direction and / or in a direction perpendicular to the optical axis.
The light transmission device according to claim 1. 3. The heat insulating member has a spring washer shape,
The light transmission device according to claim 1, wherein one end of the light transmission member contacts the light blocking member, and the other end contacts the light guide holding mechanism.