JP2002267909A - Optical lens clamping device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make high the precision of the clamping and positioning of respective lenses in the redial and optical-axis directions when the temperature varies by pressing the lens in the ratial direction and optical axis direction when lens spherical parts are clamped. SOLUTION: The optical lens clamping device is equipped with a lens barrel CE, lenses L1 to L4 in order in the incidence direction of laser light, shrink fitters (clamping member) SS and SB, and a pacer SP. The shrink fitters SS clamps the lenses L1 to L3 and the shrink fitter SB clamps the lens L4. The shrink fitter SB forms a part (1st clamping part) which clamps the circumference of the lens L4 and a part (2nd clamping part) which abuts against the spherical surface part of the lens L4 to clamp the lens L4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical lens fastening device, and more particularly to a device for incorporating an optical lens into a lens barrel by using a fastening member such as a ring made of a high thermal expansion material having a larger thermal expansion coefficient than the lens barrel. And an optical lens fastening device.

[0002]

2. Description of the Related Art In recent years, laser printers and copiers,
With the expansion of laser application fields such as laser microscopes, higher resolution and higher accuracy of laser application devices have been desired. In order to achieve such high resolution and high accuracy, it is important to increase the accuracy of a scanning lens that forms an image of a laser beam diameter over a wide scanning width in an optical system.

FIG. 7 is a longitudinal sectional view of a conventional optical lens fastening device. Also, the dimensions in the drawing show an example. The optical lens joining device in the figure includes a lens barrel 100, a scanning lens group 1
1 to 16 and a shrink fitter (fastening member) 110;
111 is provided. The lens barrel 100 can be formed of, for example, a metal such as aluminum. The lens barrel 100 includes lenses 11 to 16 and shrink fitters 110 and 111 in order from the direction in which the laser is incident (for example, the right side in the figure).
It has. The lenses 11 to 16 are joined by shrink fitters 110 and 111 in the lens barrel 100. The diameters of the lenses 11 to 16 may be different or the same, and the shape of each of the lenses 11 to 16 may be an appropriate shape such as convex or concave. The shrink fitters 110 and 111 are cylindrical mechanical elements made of a material whose coefficient of thermal expansion is larger than that of the metal lens barrel 100 such as aluminum. In the conventional optical lens fastening device, the shrink fitters 110 and 111 can be used to perform an interference fit.

[0004]

However, in the conventional fastening method using a fastening member such as a ring made of a high thermal expansion material for an optical lens and a lens barrel, if the ring made of the high thermal expansion material is thin, the fastening is performed when the temperature changes. In some cases, loosening of parts occurred. In addition, in the fastening method using a fastening member such as a ring made of a high thermal expansion material, the position of each lens in the optical axis direction fluctuates due to deformation due to thermal expansion of the material in the optical axis direction when the temperature changes. It was.

Further, in the fastening method using a fastening member such as a ring made of a high thermal expansion material, there has been a problem that the fastening force is weakened due to aging due to the creep characteristics of the material. In addition, in the fastening method using a fastening member such as a ring made of a high thermal expansion material, the optical axis direction positioning between the lenses requires an optical axis direction positioning component such as a metal spacer. In addition, in a fastening method using a fastening member such as a ring made of a high thermal expansion material, the distance between the lenses fastened in one fastening member in the optical axis direction can be accurately positioned, but the entire lens group with respect to the lens barrel And when a plurality of fastening members are used, it is difficult to accurately position the lens groups fastened by the fastening members.

SUMMARY OF THE INVENTION In view of the above, the present invention provides an optical lens in which the spherical surface of an optical lens is fastened by a fastening member such as a material having a high thermal expansion, so that the optical lens is not affected by ambient temperature changes even when the fastening member is thin. It is an object of the present invention to provide an optical lens fastening device that enables highly accurate fastening of a lens. In addition, the present invention presses each lens in the optical axis direction with a fastening force in the lens optical axis direction generated by fastening of the lens spherical portion by a fastening member such as a ring made of a high thermal expansion material, so that the lens radius is not affected by a temperature change. It is an object of the present invention to provide an optical lens fastening device that can secure a stable fastening force in a direction and an optical axis direction. Further, the present invention provides an optical lens fastening device which performs optical axis direction positioning of an optical lens by fastening a lens spherical portion with a fastening member such as a ring made of a high thermal expansion material, and eliminates the need for an optical axis direction positioning component such as a metal spacer. The purpose is to provide.

Further, the present invention makes it possible to generate an appropriate fastening force over a long period of time by estimating the creep characteristics of a material and determining the shimeshiro in anticipation of the amount of creep deformation due to aging. An object of the present invention is to provide an optical lens fastening device. Furthermore, the present invention uses a material having anisotropy in thermal expansion and fastens the direction in which the coefficient of thermal expansion is large in the lens radial direction and the direction in which the coefficient of thermal expansion is small is aligned with the optical axis direction. It is an object of the present invention to provide an optical lens fastening device that enables highly accurate positioning between lenses when a temperature changes.

In addition, the present invention provides a method of applying a load against the static friction force between a fastening member and a lens barrel after assembling a lens and causing the lens to slide slightly in the optical axis direction, so that the optical axis of the lens group can be easily adjusted. It is an object of the present invention to provide an optical lens fastening device that is capable of adjusting a direction position and, in addition, is capable of finely adjusting a position in an optical axis direction by slightly sliding while observing a laser convergence state. And

[0009]

According to a first aspect of the present invention, there is provided one or a plurality of optical lenses having the same shape and / or different shape and / or the same diameter and / or different diameter. A lens barrel that houses the optical lens inside,
The first fastening portion is formed of a material having a thermal expansion coefficient larger than that of the lens barrel and is in contact with the circumferential portion of the optical lens, and the circumferential region of the optical lens excluding a portion where the transmitted light is scanned. A second fastening portion that is thicker in a radial direction than the first fastening portion and contacts the spherical portion of the optical lens;
And a second fastening portion that contacts the circumferential portion and the spherical portion of the optical lens respectively to fix the optical lens in the radial direction, and includes a fastening member for fastening the lens barrel and the optical lens, Provided is an optical lens fastening device that ensures stable fastening regardless of a temperature change.

According to a second solution of the present invention, one or a plurality of optical lenses having the same shape and / or different shape and / or the same diameter and / or different diameter, and the optical lens are housed therein. And a first fastening portion formed of a material having a larger coefficient of thermal expansion than the lens barrel and in contact with a circumferential portion of the optical lens; For the circumferential area, the first
A second fastening portion that is thicker in the radial direction than the fastening portion and contacts the spherical portion of the optical lens, and the second fastening portion contacts the spherical portion of the optical lens to fix the optical lens in the optical axis direction. An optical lens fastening device including the lens barrel and a fastening member for fastening the optical lens to ensure stable fastening regardless of a temperature change.

According to a third solution of the present invention, one or a plurality of optical lenses having the same shape and / or a different shape and / or the same diameter and / or a different diameter, and the optical lens are housed therein. And a first fastening portion formed of a material having a larger coefficient of thermal expansion than the lens barrel and in contact with a circumferential portion of the optical lens; For the circumferential area, the first
A second fastening portion which is thicker in the radial direction than the fastening portion and is in contact with the spherical portion of the optical lens, and which is positioned in the optical axis direction by fastening the optical lens to the spherical portion by the second fastening portion. The present invention provides an optical lens fastening device including the lens barrel and a fastening member for fastening the optical lens, and ensuring stable fastening regardless of a temperature change.

[0012]

DETAILED DESCRIPTION OF THE INVENTION Optical Lens Fastening Device FIG. 1 is a configuration diagram of a first embodiment of an optical lens fastening device according to the present invention. Note that the dimensions, angles, and the like in the drawings are merely examples, and the present invention is not limited thereto, and appropriate dimensions, angles, and the like can be used. Figure 1
As shown in the vertical cross-sectional view of (A), this optical lens fastening device includes a lens barrel CE and a lens in order from a laser incident direction.
L1 to L4, shrink fitter (fastening member) SS, SB, spacer SP. Shrink fitter SS, lens L1
To L3, and the shrink fitter SB has a lens L4. In this example, a plurality of lenses L1 to L4 and shrink fitters SS and SB are provided, but the number can be changed as appropriate, and one case may be used.

FIG. 1B is an enlarged view of a portion surrounded by a circle in FIG. 1A. As shown in the figure, the shrink fitter SB to which the lens L4 is fastened has a relatively small radial thickness at a portion (first fastening portion) at which the circumference of the lens L4 is fastened (see FIG. 2). This part may become loose due to a rise in temperature. Therefore, a portion (second fastening portion) where the shrink fitter SB hits the spherical portion of the lens L4 is formed.
The lens L4 is fastened using such a shrink fitter SB. The fastening force of the lens L4 is applied to the lens in the axial direction and the radial direction as indicated by arrows in the figure.
By doing so, even if the lens barrel expands and the first fastening portion (in the figure) on the circumference of the lens L4 is thin and the fastening is loose due to the temperature rise, the lens L4 spherical surface is fastened. Since the second fastening portion (shown in the drawing) is thick in the radial direction and has a large amount of thermal expansion, the fastening force of the lens L4 is maintained. in this case,
The fastening force on the lens spherical surface by the shrink fitter SB is applied not only in the radial direction but also in the optical axis direction. Also, lens L4
Is pressed by the spacer fastened in contact with the spherical surface on the opposite side to the optical axis, so that the position of the lens L4 in the optical axis direction does not change. Here, as an example, the case where the spherical surface on the opposite side of the fastening is pressed by the spacer is described, but the present invention is not limited to this, and the case where the spherical surface is fastened with the shrink fitter SB on both sides is used. Also, the present invention can be applied to a case where the opposite side of the fastening is pressed by a holding lid or the like.

FIG. 1C is a right side view of FIG. 1A. As shown in the drawing, the shrink fitter SB has a second fastening portion so that the spherical surface of the scanning area (in the figure) does not hinder the transmission of light such as laser on the lens L4 spherical surface so that the shrink fitter SB does not engage. A notch is provided in the lens L4 or the second fastening portion is not provided, so that the lens L4
Is not concluded. Here, an example in which the laser is transmitted only in one scanning direction is described as an example.However, the invention is not limited to this. When scanning in a plurality of directions, the notch is formed so as not to obstruct the transmitted light such as the laser. It can be applied in various ways by providing a part and fastening. Also, here, as an example, a description is given of a case where the lens L4 is fastened on the lens spherical surface on the laser emission side, but for each lens spherical surface only the laser incident side, only the emission side or both sides may be appropriately fastened. It is possible, and it is also possible to provide a notch as appropriate. This point can be similarly applied to the shrink fitter of another lens.

The shrink fitter may have an appropriate number of slits SL in the radial direction of the lens group. This slit may be provided so as to completely divide the shrink fitter, or may be left unpartitioned so as not to be divided. In this example, six slits SL are provided every 30 °, and the shrink fitter SB is divided into six parts. By inserting the above-mentioned slit SL in the shrink fitter in the radial direction and optimizing the thickness of the shrink fitter, it is possible to effectively utilize the thermal expansion of the shrink fitter in the radial direction, and to prevent the reduction of shrinkage. It becomes possible.

FIG. 2 is a configuration diagram of a second embodiment of the optical lens fastening device according to the present invention. As shown in the vertical cross-sectional view of FIG. 2A, this optical lens fastening device includes a lens barrel CE, lenses L1 to L4, a shrink fitter ( Fastening member) SS, SB, spacer SP. Shrink fitter SS fastens lenses L1 to L3 and shrink fitter SB
Has fastened the lens L4. In this example, lenses L1
Although a plurality of L4s and shrink fitters SS and SB are provided, the number can be changed as appropriate, and a single case may be used.

The fixing of the lenses L1 to L4 in the radial direction is performed by tightening a circumferential portion and a spherical portion of the lens. FIG. 2 (B)
2C and 2C show enlarged views of the left and right circled portions in FIG. 2A, respectively. As shown in FIG. 2 (B), the lens L4 is tightened not only in the radial direction of the lens but also in the radial direction of the lens by tightening the lens spherical portion of the shrink fitter SB (second fastening portion).
A fastening force in the optical axis direction also occurs. Further, as shown in FIG. 2C, the end face in the optical axis direction of the lens L1 on the laser incident side (for example, the left side in the figure) of the lens L1 is a shrink fitter SS (second fastening portion) and a lens barrel CE. (See arrow in the figure). Therefore, the fastening force generated in the optical axis direction of the lens spherical surface of the lens L4 is the spacer SP,
The power is transmitted to the lens L1 via the lenses L3 and L2, and the reaction force is generated at the fastening portion of the laser incident side end surface of the lens L1, whereby the lenses L1 to L4 are fixed. This makes it possible to minimize the amount of change in the positions of the lenses L1 to L4 in the optical axis direction regardless of the temperature change. Here, as an example, the case where one of the surfaces to be pressed in the optical axis direction is a plane like the lens L1 is described, but the present invention is not limited to this, and the lens surfaces at both ends of the lens group are spherical or flat. However, the present invention can be applied to an appropriate surface shape. Also, as in the first embodiment, the portions of the shrink fitters SS and SB that come into contact with the spherical surfaces of the lenses L1 and L4 are fastened to each other so that the laser transmission on the lens spherical surfaces is not hindered. Can not be.

FIG. 3 shows a configuration diagram of a third embodiment of the optical lens fastening device according to the present invention. This optical lens fastening device includes a lens barrel CE, lenses L1 to L6, and a shrink fitter (fastening member) SF in order from the direction of incidence of the laser. Here, a plurality of lenses L1 to L6 and a single shrink fitter SF are provided, but the number of each can be changed as appropriate.

The fixing of the lenses L1 to L6 in the radial direction is performed by tightening the circumferential portion of the lens with a shrink fitter SF, and as shown in the longitudinal sectional view of FIG. The fixing is performed by a fastening portion corresponding to the lens spherical surface of the shrink fitter SF. As shown in the figure, the shrink fitter SF hits each spherical surface of the lenses L1 to L6 and adjusts the length x1 to x4 of the portion where the shrink fitter SF is fastened in the optical axis direction without using a conventional metal spacer or the like. Next, the positioning between the lenses is performed. FIG. 3B is an enlarged view of a portion surrounded by a circle in FIG. For a concave lens, a groove SM is provided in the shrink fitter SF in a radial direction over a part or the entire circumference, and a portion having a shape such that the circumferential portion of the lens does not hit the shrink fitter SF (second portion). By forming the fastening portion, positioning between lenses and adaptation to lens fastening are possible. Here, as an example, lenses L1 to
The positioning of the L6 in the optical axis direction has been described, but the present invention is not limited to this. The end surface of the lens barrel CE and each of the lenses L1 to L6
It can also be applied to positioning between them. Further, as in the case of the first embodiment, the shrink fitter SF may be configured so that the spherical surface of the scanning area is not fastened so as not to hinder laser transmission on the lens spherical surface.

FIG. 4 is a block diagram showing a fourth embodiment of the optical lens fastening device according to the present invention. This optical lens fastening device includes a lens barrel CE and a lens L1 as in the above-described embodiment.
~ L4, shrink fitter SG, rod (adjustment structure) RD,
It includes a prism PL, a focus detection element DT, a laser diode LD, and a laser diode substrate LB. In this optical lens fastening device, the optical lenses L1 to L4 are fixed by the frictional force of the fastening portion of the shrink fitter SG. The shrink fitter SG and the lens barrel CE are also fixed by frictional force. The outer surface (the side in contact with the lens barrel CE) of the shrink fitter SG may be flat or smooth, or the surface may be roughened or undulated to adjust the frictional force. In addition,
A groove may be provided in the moving direction of the shrink fitter SG. Further, the rod RD is joined or fitted to the shrink fitter SG. The plurality of rods RD are arranged at appropriate angles (for example, 120 °), and the inclination of the lens can be adjusted for each circumferential direction. With such a configuration, the position of the lens in the optical axis direction can be finely adjusted by slightly sliding the shrink fitter SG with the rod RD. In addition, the operator can perform fine adjustment while observing the laser convergence state using the detection element DT.
That is, a part of the end face and / or the circumferential surface of the shrink fitter SG is slightly pushed or pulled by the rod RD with a load equal to or more than the static friction force acting between the barrel CE and the shrink fitter SG, and the barrel The position of the entire lens group with respect to CE can be adjusted with high precision. Further, when each lens is fastened by a plurality of shrink fitters SG, the position between the lens groups fastened by the shrink fitters SG can be adjusted with high accuracy. At this time, by applying a little heat to reduce the frictional force between the shrink fitter SG and the lens barrel CE, positioning can be performed more accurately.

As described in the above embodiments, in the optical lens fastening device according to the present invention, the shrink fitter can be assembled by shrink fitting or press fitting, and the shrink fitter can be pushed out by a load greater than the static friction force. Disassembly is easily possible by pulling. The lens barrel can be formed of, for example, a metal such as aluminum. In addition, as an example of the shrink fitter, a polyacetal (POM, Polyacetal) heat-resistant polymer material such as polyimide or acrylic can be used as a material. In the optical lens fastening device of the present invention, the interference fit is enabled by using such a shrink fitter. Shrink Fitter S
Each of S, SB, and SF may have a groove in the circumferential direction of the outer periphery surrounding the lens group, and this groove can be provided as needed. The groove can fix the shrink fitter joining the lens groups by passing a wire, a string, or the like.

B. Material of Shrink Fitter (fastening member) The material of the shrink fitter will be described below.
The material of the shrink fitter is a material having a larger coefficient of thermal expansion than the lens barrel. In the conventional optical lens fastening device, the case where the material of the lens barrel is a metal such as aluminum is described. However, the present invention is not limited to this, and a material other than a metal such as a resin may be used. The shrink fitter is also exemplified by a resin material such as polyacetal, polyimide, or acrylic, but is not limited thereto, and a material having a larger thermal expansion coefficient than the lens material can be used.

FIG. 5 is an illustration of the creep characteristic of the optical lens fastening member according to the present invention. This figure shows an example in which the change over time of the apparent elastic modulus at each storage temperature of polyacetal was experimentally obtained. FIG.
FIG. 4 is an explanatory diagram of a temporal change of a tightening pressure of the optical lens fastening device according to the present invention. FIG. 6 (A) is a diagram showing the tightening when the time elapses after the lenses L1 to L4 are fastened in the optical lens fastening device according to the first or second embodiment based on the elastic modulus of FIG. 9 shows an example of a result of analyzing a pressure decrease rate. As shown in the figure, it can be seen that the tightening pressure decreases greatly up to several hundred hours at the beginning of fastening, and the change after that is very small. FIG. 6B shows that the fastening member (shrink fitter) is set at a low temperature (about -15 ° C.), a normal temperature (about 25 ° C.), and a high temperature (about 70 ° C.).
(° C.) shows the rate of decrease in the tightening pressure of each lens L1 to L4 when several thousand hours have passed. As shown in the figure, it can be seen that the reduction rate differs at each temperature. In consideration of these facts, by estimating the amount of creep deformation due to secular change after fastening, and by applying a large amount of shrinkage at the initial stage, it is possible to generate an appropriate fastening force for a long period of time.

As shown in FIG. 5, when the POM is stored while being tightened in an environment of 70 ° C., the creep greatly progresses in the first several hundred hours, and the apparent elastic modulus becomes the initial value (2,417 MPa).
From about 1,700MPa at a stretch to about 700MPa. After that, even if time elapses, the elastic modulus stays at around 700 MPa, and the amount of change therefrom decreases. That is, as an example, assuming that the elastic modulus of POM is 700 MPa at the time of design,
It is possible to numerically analyze a shimeshiro that generates a target tightening pressure. This value is larger than the value obtained when the elastic modulus of the POM is obtained as the initial value of 2,417 MPa, and the larger amount is the additional amount. When tightening with the determined shimeshiro, the elastic modulus is initially 2,417 MPa, which means that it will be overtightened, but will converge to the target tightening pressure due to the creep phenomenon several hundred hours after tightening. Since the apparent elastic modulus does not substantially change even after a lapse of time, a stable tightening can be obtained with a very small decrease in the tightening pressure. The apparent decrease in the elastic modulus differs at each temperature. However, it is desirable that the materials have the same or similar apparent decrease in elastic modulus in the storage temperature range (that is, the materials have the same or similar creep characteristics).

In the fastening member according to the present invention,
The change converges in a short time after tightening, the change after that is small,
Further, by using a material having no difference in characteristics at each storage temperature, it is possible to easily estimate the shimeshiro given at the initial stage.

Here, the results in the case where polyacetal (POM, Polyacetal) is used as the fastening member for the lens system shown in FIG. 1 are shown. However, the present invention is not limited to this, and other optical lenses are not limited thereto. Also, the present invention can be applied to a fastening device using a fastening member. Furthermore, here, the fastening device in the present invention has been described,
The present invention is not limited to this, and can be applied to all optical lens fastening devices using a ring made of a high thermal expansion material.

In the optical lens fastening device according to the present invention,
Fastening is performed by tightening the circumference of the optical lens and / or the spherical portion of the lens in the radial direction. Therefore, in the fastening device of the present invention, a material having anisotropic thermal expansion coefficient, such as a liquid crystal polymer, is used for the fastening member, a direction in which the coefficient of thermal expansion is high is set in the radial direction of the lens, and a direction in which the coefficient of thermal expansion is small. Is used in the direction of the optical axis, it is possible to minimize the change in position in the direction of the optical axis while maintaining the lens holding force even when the temperature changes. Here, a liquid crystal polymer is given as an example, but is not limited thereto.
Similarly, the same effect can be obtained by using a material having a property that the thermal expansion is large in one direction and the thermal expansion is small in the other direction.

Although the optical lens fastening device according to the first to fourth embodiments of the present invention has been described herein, the present invention is not limited to this, and all high thermal expansion material rings and the like can be used. The present invention can be applied to an optical lens fastening device.

[0029]

According to the present invention, as described above, in particular,
By fastening the spherical surface of the optical lens with a fastening member such as a high thermal expansion material, it is possible to fasten the optical lens with high accuracy without being affected by changes in the surrounding temperature even when the fastening member is thin. Further, according to the present invention, by pressing each lens in the optical axis direction with a fastening force in the lens optical axis direction generated by fastening of the lens spherical portion by a fastening member such as a ring made of a high thermal expansion material,
Regardless of the temperature change, a stable fastening force in the lens radial direction and the optical axis direction can be secured. Further, according to the present invention, the optical lens is positioned in the optical axis direction by fastening the spherical portion of the lens with a fastening member such as a ring made of a high thermal expansion material, and an optical axis direction positioning component such as a metal spacer is unnecessary.

Further, according to the present invention, it is possible to estimate a creep characteristic of a material and determine a shrinkage in advance in anticipation of a creep deformation amount due to aging, so that an appropriate fastening force can be generated for a long period of time. did. Furthermore, according to the present invention, by using a material having anisotropy in thermal expansion, the direction in which the thermal expansion coefficient is large is aligned with the lens fastening direction, and the direction in which the thermal expansion coefficient is small is aligned with the optical axis direction. This enables highly accurate positioning between lenses when the temperature changes.

Further, according to the present invention, after the lens is assembled, a load against the static frictional force between the fastening member and the lens barrel is applied to slightly slide in the optical axis direction, so that the light of the lens group can be easily adjusted. The position in the axial direction can be adjusted. In addition, the position in the optical axis direction can be finely adjusted by slightly sliding while observing the convergence state of the laser.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a first embodiment of an optical lens fastening device according to the present invention.

FIG. 2 is an explanatory view of a second embodiment of the optical lens fastening device according to the present invention.

FIG. 3 is an explanatory view of a third embodiment of the optical lens fastening device according to the present invention.

FIG. 4 is an explanatory view of a fourth embodiment of the optical lens fastening device according to the present invention.

FIG. 5 is an explanatory diagram of creep characteristics of the optical lens fastening member according to the present invention.

FIG. 6 is an explanatory diagram of a temporal change of a tightening pressure of the optical lens fastening device according to the present invention.

FIG. 7 is a longitudinal sectional view of a conventional optical lens fastening device.

[Explanation of symbols]

 L1 ~ L6 Lens CE Barrel SS, SB, SF, SG Shrink Fitter SP Spacer SL Slit

Continued on the front page (71) Applicant 300089563 Kimio Omata 1-1-21, Ootakubo, Urawa-shi, Saitama (72) Inventor Isamu 1130-9, Terachi, Niigata-shi, Niigata (72) Inventor Akihiro Sugano Niigata, Niigata 2-9-2 Ichimatsu Kaigaoka Raffine Matsukaigaoka 202 (72) Inventor Kimio Omata 1-1-21 Ootakubo, Urawa-shi, Saitama F-term (reference) 2H044 AA08 AA16 AA17 AA20 AH04 AH14

Claims (9)

[Claims] A single or a same and / or a different shape and / or a plurality of optical lenses of the same diameter and / or different diameters, a lens barrel containing the optical lens therein, and a thermal expansion coefficient A first fastening portion formed of a material larger than the lens barrel and in contact with a circumferential portion of the optical lens; and a first fastening portion with respect to a circumferential region of the optical lens excluding a portion scanned by transmitted light. A second fastening portion that is thicker in the radial direction and contacts a spherical portion of the optical lens;
And a second fastening portion that contacts the circumferential portion and the spherical portion of the optical lens respectively to fix the optical lens in the radial direction, and includes a fastening member for fastening the lens barrel and the optical lens, An optical lens fastening device that ensures stable fastening regardless of temperature changes. 2. An optical lens having one or the same shape and / or a different shape and / or a plurality of optical lenses having the same diameter and / or different diameter, a lens barrel accommodating the optical lens therein, and a thermal expansion coefficient. A first fastening portion formed of a material larger than the lens barrel and in contact with a circumferential portion of the optical lens; and a first fastening portion with respect to a circumferential region of the optical lens excluding a portion scanned by transmitted light. A second fastening portion that is thicker in the radial direction and contacts a spherical portion of the optical lens;
The fastening portion contacts the spherical portion of the optical lens to fix the optical lens in the optical axis direction, and includes a fastening member for fastening the lens barrel and the optical lens, and a stable fastening regardless of a temperature change. Optical lens fastening device that ensures 3. A single or a same and / or a different shape and / or a plurality of optical lenses of the same diameter and / or different diameters, a lens barrel containing the optical lens therein, and a thermal expansion coefficient. A first fastening portion formed of a material larger than the lens barrel and in contact with a circumferential portion of the optical lens; and a first fastening portion with respect to a circumferential region of the optical lens excluding a portion scanned by transmitted light. A second fastening portion that is thicker in the radial direction and contacts a spherical portion of the optical lens;
The optical lens is positioned in the optical axis direction by fastening to a spherical portion of the optical lens by a fastening portion, and the optical lens is provided with a fastening member for fastening the optical lens, which is stable regardless of a temperature change. An optical lens fastening device that secures fastening. 4. The optical lens fastening device according to claim 1, wherein the fastening member has a slit in a radial direction over a part or the entire thickness. 5. The thickness of the fastening member in the radial direction or the axial direction is based on the estimation of stress relaxation due to aging of a material, and an initial fastening amount for generating an appropriate fastening force over a long period is given. The thickness is set to be 1 to 4.
The optical lens fastening device according to any one of the above. 6. The material for the fastening member according to claim 1, wherein a primary creep deformation period is short, the subsequent deformation is small, and a change in temperature characteristics is small. Optical lens fastening device. 7. The optical lens fastening device according to claim 1, wherein the fastening member has a coefficient of thermal expansion that is high in a radial direction and low in an optical axis direction. 8. The fastening member is fixed to the lens barrel by a frictional force, and applies a load against the static frictional force between the fastening member and the lens barrel, thereby causing the load in the optical axis direction. The optical lens fastening device according to claim 1, wherein the optical lens fastening device can be slightly slid. 9. A detecting unit for observing a convergence state of light transmitted through the optical lens, and applying a load against a static friction force between the fastening member and the lens barrel to cause the light to slide slightly. The optical lens fastening device according to claim 8, further comprising: an adjustment mechanism for finely adjusting the position of the optical lens in the optical axis direction.