JPH11174212A - Production of cross dichroic prism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a cross dichroic prism to easily arrange dichroic film forming planes which are crossed to each other on almost the same plane so as to be produced efficiently and to prevent the occurrence of a double image or image blurring in the case of using the prism for a projector. SOLUTION: A joint is formed by bonding another optical member 202 having a plane to an optical member 201 in which a first dichroic film 203 is formed on its plane, the joint is cut almost perpendicularly to the bonding plane of that joint, and first and second joint halves A and B are provided. The cutting planes of these first and second joint halves A and B are ground, a second dichroic film 204 is formed on the ground plane of the first joint half A and afterwards, the ground planes of the first and second joint halves A and B are bonded so that first dichroic films 203 and 203 can be made into almost the sample plane. Thus, the first dichroic film 203 and the second dichroic film 204 can be almost mutually orthogonally arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to two kinds of dichroic films which are substantially orthogonal to each other or intersect at an arbitrary angle to separate light from a light source into light of three colors of red, green and blue. The present invention relates to a method for manufacturing a cross dichroic prism used for synthesizing colored light.

[0002]

2. Description of the Related Art FIG. 51 (a) shows a schematic configuration of a full-color projection device for synthesizing three colors using a cross dichroic prism, and FIG. 51 (b) is a perspective view of the cross dichroic prism.

In FIG. 51 (a), light emitted from a light source 101 is reflected by a dichroic mirror 102 in a range of green and blue wavelengths, and the reflected light is reflected by a dichroic mirror 103 in a green wavelength range. The light is reflected, and the green light passes through a field lens 104G and a dichroic filter 105G, is further subjected to light modulation by a transmission type modulation optical element 106G such as a liquid crystal, and enters a cross dichroic prism 120. On the other hand, the blue light transmitted through the dichroic mirror 103 is transmitted through a relay lens 107, a total reflection mirror 108, and a relay lens.
109, a total reflection mirror 110, a field lens 104B,
After passing through a dichroic filter 105B, the light is modulated by a transmissive modulation optical element 106B such as a liquid crystal and is incident on a cross dichroic prism 120. The red light transmitted through the all dichroic mirror 102 is reflected by the total reflection mirror 111,
After passing through the field lens 104R and the dichro filter 105R,
Further, the light is modulated by a transmission type modulation optical element 106R such as a liquid crystal and is incident on a cross dichroic prism 120. The modulated light of each color that has entered the cross dichroic prism 120 is synthesized by the dichroic film into three colors, and is projected by the projection lens 112 onto a screen (not shown) in front of the projection lens.

As shown in FIG. 51 (b), for example, a cross dichroic prism 120 is provided on the inner surfaces of optical glass members 121, 122, 123 and 124 each having a right-angled isosceles triangular prism shape. It has a structure in which the reflection dichroic film 120B is sandwiched therebetween. An anti-reflection film is formed on the four surfaces constituting the outer surfaces of the optical glass members 121, 122, 123, 124 constituting the cross dichroic prism 120.

FIG. 52 shows a schematic configuration of an optical pickup for an optical disk using three wavelengths for performing three-color synthesis using a cross dichroic prism.

In FIG. 52, a cross dichroic prism 120 has three different wavelengths (410n) from three directions.
m, 650 nm, and 790 nm), and these three wavelengths of light are synthesized by the cross dichroic prism 120.
The light passes through the lens 125, is reflected by the mirror 126, and is irradiated on the recording surface of the optical disk 127. In addition,
As a cross dichroic prism for an optical pickup, a prism having a size of several millimeters is usually used.

As described above, the cross dichroic prism is used for synthesizing the three-color light of the projected light. In addition, the cross dichroic prism can be used for separating the light from the white light source into three-color light.

A method for manufacturing a cross dichroic prism is described in Japanese Patent Application Laid-Open No. 9-15405. This will be described with reference to FIGS.

As shown in FIGS. 53 (a) and 53 (b), an optical member
Each of 11, 12, 13, and 14 has a right-angled isosceles triangular prism shape, and the optical members 11 and 14 are longer than the optical members 12 and 13. In advance, the optical member 11
A dichroic film 11R for reflecting red light is formed on one side (lower surface in the figure) sandwiching the right angle portion, and a dichroic film 11B for reflecting blue light is formed on the other side (surface facing the optical member 12) sandwiching the right angle portion. It is formed. A dichroic film 12 for reflecting red light is provided on one side surface (the lower surface in the figure) of the optical member 12.
R is formed. Further, no dichroic film is formed on the optical member 13, and a dichroic film 14B for reflecting blue light is formed on one side surface (the surface facing the optical member 13) of the optical member 14. As shown in FIG. 53 (a), one side of the optical member 11 and one side of the optical member 12 are bonded with an adhesive to produce a first bonding member 15, and one side of the optical member 14 and the optical member 13
Are bonded together with an adhesive to form a second bonding member 16. When performing this joining, the illustrated lower surface of the optical member 11 and the illustrated lower surface of the optical member 12 are arranged on a reference plane (not shown), and are joined with an adhesive to produce a first joining member 15. Similarly, a second joining member 16 is manufactured as shown in FIG. Next, the first and second joining members 15 and 16 are
32A and 32B are disposed on the reference surfaces 32A and 32B of a U-shaped joining jig 32 formed substantially on the same plane. At that time, FIG.
As shown in FIG. 3 (c), the dichroic films 11B and 14B for reflecting blue light, which are exposed at the protruding portions of the optical members 11 and 14, are brought into contact with the reference surfaces 32A and 32B, and the first and second dichroic films are bonded using the adhesive 20. The second joining members 15 and 16 are joined. FIG. 53 (d)
FIG. 53E is a perspective view of the cross dichroic prism thus formed, and FIG. 53E is a cross-sectional view showing a cross-sectional shape of the cross dichroic prism.

As described above, in the conventional method of manufacturing a cross dichroic prism, four right-angled isosceles triangular prisms having good angular accuracy are prepared, and a dichroic film for red light and / or blue light is provided on the side surface of each triangular prism. (11R, 12R
, 11B, 14B), the four triangular prisms were bonded with high precision. In this case, the two dichroic films for reflecting blue light 11B and 14B are arranged on substantially the same plane, and the two dichroic films for reflecting red light are arranged.
It is necessary to join such that 11R and 12R are arranged on another substantially same plane. This is because if the red light reflecting dichroic film and the blue light reflecting dichroic film are not respectively arranged on the same plane, when viewed in cross section, the films themselves on both sides at the center have steps and angles with each other, This is because a step and an angle cause a projected image to produce a double image or blur when used in a projection device or the like.

However, in the prior art shown in FIG. 53, it is difficult to manufacture a right-angled isosceles triangular prism with good angular accuracy, which is disadvantageous in terms of cost. Moreover, it is extremely difficult to obtain a plane by arranging two right-angled isosceles triangular prisms on a reference plane and bonding them together, and even when the first and second joining members that are not planar are joined, the vertices of the four triangular prisms There is a problem that does not fit. For example, even if the right angle of one right-angled isosceles triangular prism is off by 0.001 degrees, when four right-angled isosceles triangular prisms are united, a gap of several tens of μm is generated at the four vertices.

[0012]

As described above, in the conventional method of manufacturing a cross dichroic prism, it is difficult to easily form a right-angled isosceles triangular prism with good angular accuracy in advance. Further, it is difficult to arrange two right-angled isosceles triangular prisms on a reference plane and bond them together to obtain a plane. Moreover, even if the first and second joining members that are not flat are joined, four right-angled prisms are joined. There is a problem that the vertices of the equilateral triangular prism do not match. For this reason, when used in a projection device, it has been a cause of generating double images and blurring of images.

In view of the above problems, the present invention makes it easy to arrange dichroic film-forming surfaces that intersect each other in a cross dichroic prism on substantially the same plane, enabling efficient manufacture and projection. An object of the present invention is to provide a method for manufacturing a cross dichroic prism that can prevent the occurrence of double images and image blurring when used in an apparatus.

[0014]

According to a first aspect of the present invention, there is provided a method of manufacturing a cross dichroic prism, wherein two types of dichroic films are substantially orthogonal to each other, and a light source light is red, green, and red. A method for manufacturing a cross dichroic prism that separates light into three colors of blue light or enters and combines light of three colors, wherein an optical member having a first dichroic film formed on a flat surface has a flat surface. Forming a joined body by joining the optical members, and cutting the joined body substantially at right angles to the joining surface of the joined body;
A second bonding half is obtained, the cut surfaces of the first and second bonding halves are polished, and a second dichroic film is formed on the polished surface of the first bonding half. The first dichroic film is bonded to the second dichroic film by joining the film surface of the first bonding half and the polished surface of the second bonding half such that the first dichroic film forms substantially the same surface. Are arranged so as to be substantially orthogonal to each other.

According to the first invention, in the method of manufacturing a cross dichroic prism, each of the first and second dichroic films is formed on substantially the same plane, and the first and second dichroic films are substantially mutually separated. They can be arranged orthogonally. When used in a projection device, the occurrence of double images and blurring of images can be prevented.

According to a second aspect of the present invention, a method of manufacturing a cross dichroic prism is as follows.
A plurality of flat optical members having a first dichroic film formed on one surface are prepared, and these are laminated and joined so that the film surfaces are substantially parallel to each other. Then, the laminate is divided into two at substantially right angles to the film surface to obtain first and second laminates. The cut surfaces of the first and second laminates are polished, and then the first and second laminates are polished. A second dichroic film is formed on the polished surface of the laminate, and the film surface of the first laminate and the polished surface of the second laminate are formed such that the first dichroic film is substantially the same plane as the first dichroic film. By bonding the first dichroic film and the second dichroic film, a repeating body in which the first dichroic film and the second dichroic film are substantially orthogonal to each other is obtained.

According to the second aspect of the present invention, when a plurality of cross dichroic prisms are manufactured, an efficient manufacturing method is made possible, and the first and second dichroic prisms are manufactured for each manufactured cross dichroic prism. Each of the films can be formed on substantially the same plane, and the first and second dichroic films can be arranged so as to be substantially orthogonal to each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented. In particular, in the case of a prism having a size of several millimeters, such as a cross dichroic prism for an optical pickup, a plurality of prisms can be efficiently formed.

According to the third aspect of the present invention, a method of manufacturing a cross dichroic prism is as follows.
A cross dichroic prism that arranges two types of dichroic films so as to form a predetermined angle with each other and separates the light source light into three colors of red, green, and blue, or that receives and combines three colors of light to manufacture a cross dichroic prism. A method, wherein a joined body is formed by joining another optical member having a plane to an optical member having a first dichroic film formed on a plane,
The joined body is cut at a predetermined angle with respect to the joining surface of the joined body to obtain first and second joined halves, and the cut surfaces of the first and second joined halves are polished. After forming a second dichroic film on the polished surface of the first bonded half, the film surface of the first bonded half and the polished surface of the second bonded half are separated by a first dichroic A method for manufacturing a cross dichroic prism, wherein the first dichroic film and the second dichroic film are arranged so as to form a predetermined angle with each other by bonding the films so as to form substantially the same plane.

According to the third invention, in the method of manufacturing a cross dichroic prism, each of the first and second dichroic films is formed on substantially the same plane, and the first and second dichroic films are fixed to each other. At an angle. When used in a projection device, the occurrence of double images and blurring of images can be prevented.

According to a fourth aspect of the present invention, a method of manufacturing a cross dichroic prism is as follows.
The manufacturing method according to any one of claims 1 to 3, wherein a low-temperature process such as sputtering or ion-assisted evaporation is used to form the second dichroic film.

According to the fourth aspect, since a low-temperature process is used to form the second dichroic film, no heat treatment is required, and therefore, the second dichroic film is bonded with an adhesive before the intermediate processing step. It is possible to prevent a situation where an abnormality occurs in a part.

According to a fifth aspect of the present invention, a method of manufacturing a cross dichroic prism is as follows.
A method for manufacturing a cross dichroic prism in which two kinds of dichroic films are made substantially orthogonal to each other to separate light source light into three colors of red, green, and blue, or to enter and combine three colors of light, Forming a joined body by joining the first optical member having a flat surface to the optical member on which the first dichroic film is formed, and cutting the joined body substantially at right angles to the joining surface of the joined body. , First and second joining halves are obtained, and the cut surfaces of the first and second joining halves are polished,
Bonding a second optical member having a separately prepared second dichroic film to the polishing surface of the first bonding half;
After removing the surface of the second optical member on the side opposite to the bonding surface to a position where the second dichroic film is not removed,
By bonding the second optical member so that the first dichroic film surface of the first bonding half and the first dichroic film surface of the second bonding half are substantially the same,
The first dichroic film and the second dichroic film are arranged so as to be substantially orthogonal to each other.

According to the fifth invention, in the method of manufacturing a cross dichroic prism, each of the first and second dichroic films is formed on substantially the same plane, and the first and second dichroic films are substantially mutually separated. They can be arranged orthogonally. When used in a projection device, the occurrence of double images and blurring of images can be prevented.

According to a sixth aspect of the present invention, a method for manufacturing a cross dichroic prism is as follows.
6. The second optical member according to claim 5, wherein the second dichroic film is formed on a substrate having etching selectivity with respect to the second dichroic film. After the dichroic film surface is bonded to the polished surface of the first bonding half, the substrate of the second optical member is removed by etching.

According to a seventh aspect of the present invention, a method for manufacturing a cross dichroic prism is as follows.
6. The structure according to claim 5, wherein the second optical member includes a base film having etching selectivity with respect to at least the second dichroic film, and the second dichroic film is formed on the base film. After the second dichroic film surface of the second optical member is bonded to the polished surface of the first bonding half, the base film of the second optical member is removed by etching. I do.

According to an eighth aspect of the present invention, a method of manufacturing a cross dichroic prism according to the present invention is as follows.
The second optical member according to claim 5, wherein the second optical member is provided on a substrate having no etching selectivity with respect to the second dichroic film,
The second dichroic film has a structure in which a base film having etching selectivity with respect to the second dichroic film is formed, and a second dichroic film is formed on the base film. After the surface is bonded to the polished surface of the first bonding half, the substrate of the second optical member is polished and removed, and the underlying film is removed by etching.

According to a ninth aspect of the present invention, a method for manufacturing a cross dichroic prism is as follows.
By preparing a plurality of first optical members on a flat plate having a first dichroic film formed on one surface, and laminating and joining them so that the film surfaces are substantially parallel, a repeating body of the first dichroic film is obtained. Then, the laminate is divided into two at substantially right angles to the film surface to obtain first and second laminates, and the cut surfaces of the first and second laminates are polished. A separately prepared second optical member on which a second dichroic film is formed is bonded to the polished surface of the first laminate, and the surface of the second optical member on the side opposite to the bonded surface is bonded to the second surface. After removing the dichroic film 2 to a place where the dichroic film is not removed, the first dichroic film surface of the first laminate and the first dichroic film of the second laminate are removed.
So that the dichroic film surfaces of
And bonding by sandwiching the above optical member to obtain a repeating half in which the first dichroic film and the second dichroic film are substantially orthogonal to each other.

According to the ninth aspect, when a plurality of cross dichroic prisms are manufactured, an efficient manufacturing method becomes possible, and the first and second dichroic prisms are manufactured for each manufactured cross dichroic prism. Each of the films can be formed on substantially the same plane, and the first and second dichroic films can be arranged so as to be substantially orthogonal to each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented. In particular, in the case of a prism having a size of several millimeters, such as a cross dichroic prism for an optical pickup, a plurality of prisms can be efficiently formed.

According to a tenth aspect of the present invention, in the method of manufacturing a cross dichroic prism, two kinds of dichroic films are arranged so as to form a predetermined angle with each other, and the light source light is red, green, and red. A method for manufacturing a cross dichroic prism that separates light into three colors of blue light or enters and combines light of three colors, wherein an optical member having a first dichroic film formed on a flat surface has a flat surface. A bonded body is formed by bonding the first optical member, and the bonded body is cut at a predetermined angle with respect to a bonding surface of the bonded body to obtain first and second bonded halves. 1, polishing the cut surface of the second bonding half, and bonding a second optical member having a separately prepared second dichroic film to the polishing surface of the first bonding half, A second optical member on the opposite side of the joining surface Is removed to the point where the second dichroic film is not removed, and then the first dichroic film surface of the first bonding half and the first dichroic film surface of the second bonding half are substantially flush with each other. As described above, the first dichroic film and the second dichroic film are arranged so as to form a predetermined angle with each other by joining the second optical member therebetween.

According to the tenth aspect, in the method for manufacturing a cross dichroic prism, each of the first and second dichroic films is formed on substantially the same plane, and
The second dichroic films can be arranged so as to form a predetermined angle with each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented.

[0031]

Embodiments of the present invention will be described with reference to the drawings. 1 to 8 are perspective views showing a method for manufacturing a cross dichroic prism according to the first embodiment of the present invention.

First, an optical member such as a glass block (BK
7) are prepared and the two surfaces of each of these glass blocks are polished on both sides to obtain optical members 201 and 202 composed of parallel plate glass blocks as shown in FIG.

Next, as shown in FIG.
The first dichroic film 20 for reflecting red light, which reflects red light and transmits blue light, on the polished surface of the glass block 201.
Form 3. Then, the first dichroic film 20
3 is bonded to the polished surface of the glass block 201, which is the other optical member 202, using an adhesive such as epoxy, so that the bonding surface shown in FIG. Get the body.

Next, as shown in FIG. 4, the joined body is cut into two to obtain first and second joined halves A and B, and the first and second joined halves A and B are obtained. Polish the cut surface.

Next, as shown in FIG. 5, a second dichroic film 204 for reflecting blue light and transmitting red light is formed on the polished surface of the first bonding half A. This blue light reflection film is formed by a low-temperature process such as sputtering or ion-assisted evaporation. According to this forming method, a dichroic film having good characteristics can be formed without heating the bonding half A in which the adhesive is already applied to the surface of the red light reflecting film 203. That is, in forming a conventional dichroic film, the adhesive (usually an epoxy-based) has a heat resistance temperature of 150.
Below about C, it was difficult to obtain a dichroic film with good characteristics.

Next, as shown in FIG. 6, the polished surfaces of the first blue light reflecting dichroic film 204 of the first bonding half A and the second bonding half B are bonded to the first bonding half A for red light reflection. So that the dichroic film 203 of the above forms the original plane (that is, the same plane),
Join with an adhesive such as epoxy.

Next, as shown in FIG. 7, the outer surfaces of the first and second dichroic films 203 and 204 for reflecting red light and blue light are cut off at 45 degrees to form an outer shape.

Next, the cut surface (four surfaces) is polished, and an antireflection film 205 is formed on the polished surface by a low-temperature process such as sputtering or ion-assisted vapor deposition to obtain a cross dichroic prism as shown in FIG. Get.

According to the first embodiment, in the method for manufacturing a cross dichroic prism, the second dichroic film 204 is formed as shown in FIG. ), The plane angle is 1
80 ° can be easily obtained, and the flatness of the first dichroic film 203 can be obtained by changing the first dichroic film 203 formed on the bonding plane of the bonded body shown in FIG. In this manner, the halves A and B are divided and the halves A and B are joined again as shown in FIG. 6, so that the original plane angle can be easily returned to 180 degrees. Therefore, the first and second dichroic films 20
3 and 204 are formed on substantially the same plane, and the first and second
These dichroic films 203 and 204 can be arranged so as to be substantially orthogonal to each other. When used in a projection device or the like, occurrence of double images and blurring of images can be prevented.

FIGS. 9 to 17 are perspective views showing a method of manufacturing a cross dichroic prism according to a second embodiment of the present invention.

First, an optical member such as a glass block (BK
7) are prepared, and two surfaces of each of these glass blocks are polished on both sides, so that a plurality of optical members 211, 212, 21 composed of a plurality of parallel plate glass blocks are prepared.
Obtain 3,214.

Then, as shown in FIG.
The first dichroic films 215, 216, and 21 for reflecting red light are provided on one surface of each of the glass blocks constituting 2, 213 and 214.
Form 7.

Next, as shown in FIG. 10, the optical members 212, 213, 214 are laminated and joined so that the film surfaces of the first dichroic films 215, 216, 217 for reflecting red light become parallel. A laminate, which is a repeat of the first dichroic film, is formed.

Next, as shown in FIG. 11, the laminate is divided into two at right angles to the film surfaces of the first dichroic films 215, 216, 217 for reflecting red light, and the first and second laminates E, F And the cut surfaces of the first and second laminates E and F are polished.

Next, as shown in FIG. 12, a second dichroic film 218 for reflecting blue light is formed on the polished surface of the first laminate E. This blue light reflection film is formed by a low-temperature process such as sputtering or ion-assisted evaporation.

Next, as shown in FIG. 13, the first dichroic films 215, 216, and 217 are formed such that the film surface of the first laminate E and the polished surface of the second laminate F are substantially the same. By bonding with an adhesive such as epoxy or the like, a repetitive body (laminated body) H in which the first dichroic films 215, 216, 217 and the second dichroic film 218 are substantially orthogonal to each other is obtained.

Next, as shown in FIG.
The dichroic films 215, 216, and 217 are divided into a plurality such that they are located at the center, and each of the divided bodies is divided into first and second dichroic films for red light reflection and blue light reflection as shown in FIG. The outer shape is cut off at 45 degrees to the film surface.

Next, the cut surface (four surfaces) thus cut is polished, and an antireflection film 219 is formed on the polished surface as shown in FIG. 16 by a low-temperature process such as sputtering or ion-assisted vapor deposition. To obtain a plurality of cross dichroic prisms.

According to the second embodiment, when a plurality of cross dichroic prisms are manufactured, an efficient manufacturing method can be achieved, and the first and second cross dichroic prisms to be manufactured can be used. Can be formed on substantially the same plane, and the first and second dichroic films can be arranged so as to be substantially orthogonal to each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented. In particular, in the manufacture of a prism having a size of several millimeters, such as a cross dichroic prism for an optical pickup, a plurality of prisms can be efficiently manufactured.

In the first and second embodiments described above, the method of manufacturing a cross dichroic prism in which the first and second dichroic films are substantially perpendicular to each other has been described. However, the present invention is substantially perpendicular to each other. The present invention is not limited to the cross dichroic prism, and can be applied to a case where a cross dichroic prism in which the first and second dichroic films intersect at an arbitrary angle as shown in FIG.

FIGS. 19 and 20 are perspective views showing a method of manufacturing a cross dichroic prism according to the third embodiment of the present invention.

This embodiment is a modification of the first embodiment, and is a joined body in which the first dichroic film 203 for reflecting red light is formed in the first embodiment (see FIG. 3). Next, as shown in FIG. 19 (a), at the predetermined angle (60 degrees in the figure) with respect to the first dichroic film 203 for reflecting red light, The first and second bonding halves A and B are obtained as described above, and the cut surfaces thereof are polished. Dichroic film 204
After the formation, the first dichroic film 203 for reflecting red light is substantially the same as the polished surface of the first bonding half A and the polished surface of the second bonding half B as shown in FIG. Join with an adhesive such as epoxy to form a surface. Thereafter, when forming the outer shape, the cross dichroic crossing at a predetermined angle as shown in FIG. 18 is performed by forming the outer shape of the second dichroic film 204 at, for example, 30 degrees as shown in FIG. Prism can be obtained.

According to the third embodiment, in a method of manufacturing a cross dichroic prism, each of the first and second dichroic films is formed on substantially the same plane, and the first and second dichroic films are formed. They can be arranged so as to form a predetermined angle with each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented.

FIGS. 21 to 30 are perspective views showing a method for manufacturing a cross dichroic prism according to the fourth embodiment of the present invention.

First, an optical member such as a glass block (BK
7) are prepared, and the two surfaces of each of these glass blocks are polished on both sides, so that optical members 201 and 202 composed of parallel plate glass blocks as shown in FIG.
Get.

Next, as shown in FIG. 22, a first dichroic film for reflecting red light, which reflects red light and transmits blue light, is polished on the polished surface of the glass block which is one of the optical members 201.
Form 203. Then, the first dichroic film 2
By bonding the film surface of the optical member 201 with the 03 formed thereon and the polished surface of the glass block as the other optical member 202 using an adhesive such as epoxy, the bonding as shown in FIG. Get the body.

Next, as shown in FIG. 24, the joined body is cut into two to obtain first and second joined halves A and B.
The cut surfaces of the second joined halves A and B are polished. Up to this point, it is the same as FIGS. 1 to 4 in the first embodiment.

Next, a second dichroic film 204 for reflecting blue light and transmitting red light is formed on one surface of the glass plate 206, and a second optical member C as shown in FIG. prepare.

Then, as shown in FIG. 26, the second optical member C on which the second dichroic film 204 prepared separately is formed on the polished surface of the first bonding half A by epoxy or the like. With an adhesive.

Next, as shown in FIG. 27, the second optical member C
The surface opposite to the bonding surface of the second dichroic film 204
Is removed by grinding, polishing, etc., to the point where is not removed. It is optimal to remove the entire glass plate 206 and leave only the second dichroic film 204. However, if the thickness of the glass plate 206 is about 20 μm, this cross dichroic Even if a prism is used for the projection device, the thickness of the glass plate has little effect on the screen.

Next, as shown in FIG. 28, the joint half shown in FIG. 27 and the second joint half B shown in FIG.
An adhesive such as epoxy with the second optical member C interposed therebetween such that the first dichroic film surface of the bonding half of the second optical member C and the first dichroic film surface of the second bonding half B are substantially the same. Join with.

Next, as shown in FIG. 29, first and second dichroic films 203, 204 for reflecting red light and blue light.
Is cut off at an angle of 45 degrees to each film surface to shape the outer shape.

Next, the cut-off shaped surface (four surfaces) is polished, and an anti-reflection film 205 is formed on the polished surface by a low-temperature process such as sputtering or ion-assisted vapor deposition. Get. Note that an antireflection sheet may be attached instead of the antireflection film 205.

According to the fourth embodiment, in the method of manufacturing a cross dichroic prism, the second dichroic film 204 is formed on one surface of a separately prepared second optical member C as shown in FIG. A cut surface (polished surface) of the bonded half shown in FIG. 24 with respect to the film surface of the optical member C.
Can be easily obtained at a plane angle of 180 degrees, and the flatness of the first dichroic film 203 is determined with respect to the first dichroic film 203 formed on the bonding plane of the bonded body shown in FIG. Is divided into joining halves A and B as shown in FIG. 24, and the divided halves A and B are joined again so as to sandwich the optical member C thinned by polishing as shown in FIG. Therefore, it can be easily returned to the original plane angle of 180 degrees. Therefore, each of the first and second dichroic films can be formed on substantially the same plane, and the first and second dichroic films can be arranged so as to be substantially orthogonal to each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented.

In the fourth embodiment, the back surface of the second optical member C is removed by grinding, polishing or the like in FIGS. 25 to 27. However, the back surface of the second optical member C is obtained by another method. There is also a method of removing. Next, the embodiment will be described.

FIGS. 31 to 33 are perspective views showing a method of manufacturing a cross dichroic prism according to the fifth embodiment of the present invention.

In the present embodiment, the back surface of the second optical member C is removed by grinding, polishing or the like in the fourth embodiment (see FIGS. 25 to 27). The method for removing the back surface of the optical member C is shown.

That is, the second dichroic film 204 for reflecting blue light is usually composed of an oxide multilayer film. Instead of the glass plate 206 in the second optical member C of FIG. 25, FIG.
In this embodiment, a substrate 207 made of a material having etching selectivity with respect to the oxide film is used. By dissolving the substrate 207 with a chemical (etching solution), only the undissolved second dichroic film is bonded to the first bonding half A and remains.

For example, as shown in FIG. 32, a second dichroic film 204 for reflecting blue light is formed on a substrate 207 using a metal which is easily soluble in an acid or alkali such as copper or aluminum.

Next, as shown in FIG. 32, the second optical member C
After bonding the second dichroic film surface to the polished surface of the first bonding half A, the substrate 207 of the second optical member C
Is dissolved in an etching solution with an acid or an alkali to obtain a bonded half as shown in FIG.

Then, a second joining half B similar to that shown in FIG. 24 is joined to the half shown in FIG.
By forming the outer shape and forming the anti-reflection film and the like as shown in FIG. 30 to FIG. 30, a cross dichroic prism as shown in FIG. 31 can be obtained.

FIGS. 34 to 37 are perspective views showing a method of manufacturing a cross dichroic prism according to the sixth embodiment of the present invention.

This embodiment is a modification of the fourth and fifth embodiments. That is, as shown in FIG. 34, instead of the glass plate 206 of the second optical member C of FIG. 25 or instead of the metal plate 207 of FIG. A metal film 207 is formed on one surface of the glass plate 206 and serves as a base film of the second dichroic film 204.

That is, as shown in FIG. 34, the second optical member C
As a substrate, a glass plate 206 having no etching selectivity with respect to the second dichroic film is used, and copper, which has etching selectivity with respect to the second dichroic film, is further provided thereon.
A metal film 207 such as aluminum is formed, and a second dichroic film for reflecting blue light is formed on the metal film 207.
Form 204.

Next, as shown in FIG. 35, the second optical member C
The second dichroic film surface and the polished surface of the first bonding half A are bonded with an adhesive such as epoxy.

Next, as shown in FIG. 36, the glass plate 206 forming the second optical member C of the joined body shown in FIG.
All are removed by polishing or the like. At this time, the metal film 207 such as copper or aluminum between the glass plate 206 and the second dichroic film 204 is polished so as to remain a little. That is, grinding and polishing are performed so that the total thickness of the second dichroic film 204 and the metal film 207 is 30 μm or less.

Thereafter, as shown in FIG. 37, if the metal film 207 such as copper or aluminum is dissolved by an etching solution with an acid or an alkali, a half as shown in FIG. 37 can be obtained.

Then, a second joint half B similar to that shown in FIG. 24 is joined to the half shown in FIG.
By forming the outer shape and forming the antireflection film and the like as shown in FIG. 30 to FIG. 30, a cross dichroic prism as shown in FIG. 30 can be obtained.

FIGS. 38 to 47 are perspective views showing a method of manufacturing a cross dichroic prism according to the seventh embodiment of the present invention.

First, an optical member such as a glass block (BK
7) are prepared, and two surfaces of each of these glass blocks are polished on both sides, thereby obtaining optical members 211, 212, 213, and 214 composed of a plurality of parallel plate glass blocks.

Then, as shown in FIG.
First dichroic films 215, 216, 217 for reflecting red light are formed on one surface of each of 2, 213, 214.

Next, as shown in FIG. 39, the optical members 212, 213, 214 are laminated and joined so that the film surfaces of the first dichroic films 215, 216, 217 for reflecting red light become parallel. A laminate, which is a repeat of the first dichroic film, is formed.

Next, as shown in FIG. 40, the laminate is divided into two at right angles to the film surfaces of the first dichroic films 215, 216 and 217 for reflecting red light, and the first and second laminates E and F are formed. And the cut surfaces of the first and second laminates E and F are polished.

Next, as shown in FIG. 41, a second optical member G on which a second dichroic film 218 for reflecting blue light is formed is separately prepared.

Next, as shown in FIG. 42, a second dichroic film for reflecting blue light of the second optical member G shown in FIG. 41 is formed on the polished surface of the first laminate E shown in FIG. 218 is bonded with an adhesive such as epoxy. Then the second
The surface of the glass plate 220 opposite to the bonding surface of the optical member G is removed to a position where the second dichroic film 218 is not removed. It is optimal to remove the entire glass plate 220 so that only the second dichroic film 218 remains, but the thickness of the glass plate 220 is 20 μm.
To the extent that this cross dichroic prism is used in a projection device, the thickness of the glass plate has little effect on the screen.

Thereafter, as shown in FIG. 43, with respect to the surface of the optical member G in the joined body of the first laminate E and the second optical member G (the glass plate 220 is almost removed). ,
The polished surface of the second laminate F shown in FIG. 40 is joined with an adhesive such as epoxy. At this time, the first laminate E
The first dichroic film and the second dichroic film are bonded together so that the first dichroic film surface of the second laminated body F forms substantially the same surface with the first dichroic film and the second dichroic film. To obtain a repetitive body (laminate) H in which the dichroic films are substantially orthogonal to each other.

Next, as shown in FIG. 44, the first dichroic films 215, 216, and 217 for reflecting red light are divided into a plurality of parts so as to be located at the center. The outer surfaces of the first and second dichroic films 215 and 218 for light reflection and blue light reflection are cut off at 45 degrees and shaped.

Next, the cut outer shape shaping surface (4
Surface), and the antireflection film 219 is formed on the polished surface as shown in FIG.
Is formed by a low-temperature process such as sputtering or ion-assisted vapor deposition, and then sliced as shown in FIG. 47 to obtain a plurality of cross dichroic prisms.

According to the seventh embodiment, when a plurality of cross dichroic prisms are manufactured, an efficient manufacturing method can be achieved, and the first and second cross dichroic prisms to be manufactured can be used. Can be formed on substantially the same plane, and the first and second dichroic films can be arranged so as to be substantially orthogonal to each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented. In particular, in the case of a prism having a size of several millimeters, such as a cross dichroic prism for an optical pickup, a plurality of prisms can be efficiently formed.

In the fourth to seventh embodiments described above, the method of manufacturing a cross dichroic prism in which the first and second dichroic films are substantially orthogonal to each other has been described. However, the present invention is substantially orthogonal to each other. The present invention is not limited to the cross dichroic prism but can be applied to a case where a cross dichroic prism in which the first and second dichroic films intersect at an arbitrary angle as shown in FIG.

FIGS. 49 and 50 are perspective views showing a method of manufacturing a cross dichroic prism according to the eighth embodiment of the present invention.

In this embodiment, when the joined body (see FIG. 23) on which the red dichroic film 203 as the first dichroic film is formed in the fourth embodiment (see FIG. 23) is next cut into two pieces, As shown in FIG. 49A, a predetermined angle (60 in FIG. 49) with respect to the first dichroic film 203 for reflecting red light is used.
) To obtain first and second joined halves A and B, as shown in FIG.
After bonding the second optical member C on which the separately prepared second dichroic film 204 for reflecting blue light is formed to the polished surface, the surface opposite to the bonding surface of the second optical member C is bonded. Then, the second dichroic film 204 is removed until it is not removed. Thereafter, as shown in FIG. 49 (c), the halves of FIG. 49 (b) are joined together with the first dichroic film surface of the first bonding half A and the first dichroic film surface of the second bonding half B. To
The first dichroic film 203 and the second dichroic film 204 are formed so as to form a predetermined angle by bonding the second optical member C with an adhesive such as epoxy so as to form substantially the same plane. Can be placed. Then, when forming the outer shape, as shown in FIG. 50, the second dichroic film 204 is formed.
By performing an external shape shaping to, for example, 30 degrees, a cross dichroic prism crossing at a predetermined angle as shown in FIG. 48 can be obtained.

According to the eighth embodiment, in a method of manufacturing a cross dichroic prism, each of the first and second dichroic films is formed on substantially the same plane, and the first and second dichroic films are formed. They can be arranged so as to form a predetermined angle with each other. When used in a projection device, the occurrence of double images and blurring of images can be prevented.

[0094]

As described above, according to the method for manufacturing a cross dichroic prism of the present invention, the first and second dichroic film forming surfaces intersecting each other in the cross dichroic prism can be arranged on substantially the same plane. It can be easily and efficiently manufactured, and can prevent double images and blurring of images when used in a projection device.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a method for manufacturing a cross dichroic prism according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a method of manufacturing the cross dichroic prism according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a method of manufacturing the cross dichroic prism according to the first embodiment of the present invention.

FIG. 4 is a perspective view showing a method for manufacturing the cross dichroic prism according to the first embodiment of the present invention.

FIG. 5 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the first embodiment of the present invention.

FIG. 6 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the first embodiment of the present invention.

FIG. 7 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the first embodiment of the present invention.

FIG. 8 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the first embodiment of the present invention.

FIG. 9 is a perspective view illustrating a method for manufacturing a cross dichroic prism according to the second embodiment of the present invention.

FIG. 10 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to a second embodiment of the present invention.

FIG. 11 is a perspective view showing a method for manufacturing a cross dichroic prism according to the second embodiment of the present invention.

FIG. 12 is a perspective view illustrating a method for manufacturing a cross dichroic prism according to the second embodiment of the present invention.

FIG. 13 is a perspective view showing a method for manufacturing a cross dichroic prism according to the second embodiment of the present invention.

FIG. 14 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the second embodiment of the present invention.

FIG. 15 is a perspective view showing a method for manufacturing a cross dichroic prism according to the second embodiment of the present invention.

FIG. 16 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the second embodiment of the present invention.

FIG. 17 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the second embodiment of the present invention.

FIG. 18 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the third embodiment of the present invention.

FIG. 19 is a perspective view showing a method for manufacturing a cross dichroic prism according to the third embodiment of the present invention.

FIG. 20 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the third embodiment of the present invention.

FIG. 21 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to a fourth embodiment of the present invention.

FIG. 22 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 23 is a perspective view illustrating a method for manufacturing a cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 24 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to a fourth embodiment of the present invention.

FIG. 25 is a perspective view showing a method for manufacturing a cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 26 is a perspective view illustrating a method for manufacturing a cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 27 is a perspective view illustrating a method for manufacturing a cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 28 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 29 is a perspective view illustrating a method for manufacturing a cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 30 is a perspective view showing a method for manufacturing a cross dichroic prism according to the fourth embodiment of the present invention.

FIG. 31 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to a fifth embodiment of the present invention.

FIG. 32 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to a fifth embodiment of the present invention.

FIG. 33 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to a fifth embodiment of the present invention.

FIG. 34 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to the sixth embodiment of the present invention.

FIG. 35 is a perspective view showing a method of manufacturing the cross dichroic prism according to the sixth embodiment of the present invention.

FIG. 36 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the sixth embodiment of the present invention.

FIG. 37 is a perspective view illustrating a method of manufacturing the cross dichroic prism according to the sixth embodiment of the present invention.

FIG. 38 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 39 is a perspective view showing a method of manufacturing the cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 40 is a perspective view showing a method of manufacturing the cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 41 is a perspective view showing a method of manufacturing the cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 42 is a perspective view illustrating a method of manufacturing a cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 43 is a perspective view showing a method of manufacturing the cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 44 is a perspective view showing a method of manufacturing the cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 45 is a perspective view showing a method for manufacturing a cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 46 is a perspective view showing a method of manufacturing the cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 47 is a perspective view showing a method of manufacturing the cross dichroic prism according to the seventh embodiment of the present invention.

FIG. 48 is a perspective view showing a method of manufacturing the cross dichroic prism according to the eighth embodiment of the present invention.

FIG. 49 is a perspective view showing a method of manufacturing the cross dichroic prism according to the eighth embodiment of the present invention.

FIG. 50 is a perspective view showing a method of manufacturing the cross dichroic prism according to the eighth embodiment of the present invention.

FIG. 51 shows an example of using a cross dichroic prism.
FIG. 1 is a diagram illustrating a schematic configuration of a full-color projection device that performs color synthesis, and a perspective view of a cross dichroic prism used in the device.

FIG. 52 shows an example of using a cross dichroic prism.
FIG. 2 is a diagram illustrating a schematic configuration of an optical pickup for an optical disk using three wavelengths for performing color synthesis.

FIG. 53 is a perspective view showing an example of a method for manufacturing a conventional cross dichroic prism.

[Explanation of symbols]

 201, 202: Optical member 203: First dichroic film for red light reflection 204: Second dichroic film for blue light reflection 211-214: Optical member 215-217: First dichroic film for red light reflection 218: second dichroic film for reflecting blue light A, B: first and second bonding halves C, G: second optical member E, F: first and second stacked bodies H: repeating body

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Futa Ishii 33, Shinisogo-cho, Isogo-ku, Yokohama-shi, Kanagawa Inside Toshiba Production Technology Laboratory Co., Ltd.

Claims (10)

[Claims] 1. A method of manufacturing a cross dichroic prism in which two kinds of dichroic films are made substantially orthogonal to each other to separate light source light into light of three colors, red, green and blue, or to make light of three colors incident and combine them. A joined body is formed by joining another optical member having a plane to an optical member having a first dichroic film formed on a plane, and the joined body is formed substantially at right angles to a joining surface of the joined body. Is cut to obtain first and second joint halves.
After the cut surface of the bonding half of the first is polished and a second dichroic film is formed on the polished surface of the first bonding half, the first
The first dichroic film and the second dichroic film are bonded to each other so that the first dichroic film and the polished surface of the second bonding half are substantially coplanar with each other. A method for manufacturing a cross dichroic prism, comprising arranging dichroic films so as to be substantially orthogonal to each other. 2. A method for preparing a first dichroic film by preparing a plurality of flat optical members having a first dichroic film formed on one surface thereof and laminating and joining them so that the film surfaces are substantially parallel. A laminated body as a repetitive body was prepared, and then the laminated body was divided into two at substantially right angles to the film surface to obtain first and second laminated bodies, and the cut surfaces of the first and second laminated bodies were polished. Thereafter, a second dichroic film is formed on the polished surface of the first laminate, and the first dichroic film is substantially flush with the polished surface of the first laminate and the second laminate. A manufacturing method of a plurality of cross dichroic prisms, wherein a repeating body in which the first dichroic film and the second dichroic film are substantially orthogonal to each other is obtained. 3. Two kinds of dichroic films are arranged so as to form a predetermined angle with each other, and light from a light source of three colors of red, green and blue is provided.
A method for manufacturing a cross dichroic prism that separates light into three colors or makes three colors of light incident and combines them, wherein an optical member having a first dichroic film formed on a flat surface and another optical member having a flat surface To form a joined body, and cut the joined body at a predetermined angle with respect to the joining surface of the joined body to obtain first and second joined halves. Polishing the cut surface of the first bonding half, forming a second dichroic film on the polished surface of the first bonding half, and then bonding the film surface of the first bonding half to the second bonding half. Bonding the polished surface of the body so that the first dichroic film forms substantially the same plane, thereby arranging the first dichroic film and the second dichroic film so as to form a predetermined angle with each other. A method for manufacturing a cross dichroic prism, characterized by comprising: 4. The cross dichroic prism according to claim 1, wherein a low-temperature process such as sputtering or ion-assisted vapor deposition is used to form the second dichroic film. Manufacturing method. 5. A method for manufacturing a cross dichroic prism in which two kinds of dichroic films are made substantially orthogonal to each other to separate light source light into light of three colors, red, green and blue, or to make light of three colors incident and combine them. A bonded body is formed by bonding a first optical member having a flat surface to an optical member having a first dichroic film formed on a flat surface, and the bonding member is formed substantially at right angles to a bonding surface of the bonded body. The body is cut to obtain first and second joint halves, the cut surfaces of the first and second joint halves are polished, and separately prepared on the polished surface of the first joint half. After joining the second optical member on which the formed second dichroic film is formed, removing the surface of the second optical member on the side opposite to the joining surface to a position where the second dichroic film is not removed A first dichroic film surface of the first bonding half and a second bonding half The first dichroic film and the second dichroic film are bonded to each other by sandwiching the second optical member so that the first dichroic film surface of the body forms substantially the same plane, so that the first dichroic film and the second dichroic film are substantially orthogonal to each other. A method for manufacturing a cross dichroic prism, comprising: 6. The second optical member has a structure in which a second dichroic film is formed on a substrate having an etching selectivity with respect to the second dichroic film. 6. The cross dichroic prism according to claim 5, wherein the substrate of the second optical member is removed by etching after the second dichroic film surface is bonded to the polished surface of the first bonding half. Manufacturing method. 7. The second optical member has a structure in which at least a base film having etching selectivity with respect to the second dichroic film is provided, and the second dichroic film is formed on the base film. After the second dichroic film surface of the second optical member is bonded to the polished surface of the first bonding half, the base film of the second optical member is removed by etching. The method for manufacturing a cross dichroic prism according to claim 5. 8. The second optical member is provided on a substrate having no etching selectivity with respect to a second dichroic film.
A base film having etching selectivity with respect to the dichroic film is formed, and a second dichroic film is formed on the base film. The surface of the second dichroic film of the second optical member is 6. The semiconductor device according to claim 5, wherein after being bonded to the polishing surface of the first bonding half, the substrate of the second optical member is polished and removed, and the underlying film is removed by etching. A method for producing the cross dichroic prism described in the above. 9. A first optical member on a flat plate having a first dichroic film formed on one surface is prepared, and the first optical members are laminated and joined so that the film surfaces are substantially parallel to each other.
A laminate, which is a repetition of the dichroic film, is formed, and then the laminate is divided into two at substantially right angles to the film surface to obtain first and second laminates, and cutting of the first and second laminates After polishing the surface, a second optical member on which a separately prepared second dichroic film is formed is joined to the polished surface of the first laminate, and the second optical member is opposed to the joining surface of the second optical member. The side face
After removing the dichroic film to a position where the dichroic film is not removed, the first dichroic film surface of the first laminate and the second dichroic film surface are removed.
The first dichroic film and the second dichroic film are bonded to each other by sandwiching the second optical member so that the first dichroic film surface of the laminated body forms substantially the same plane. A method for manufacturing a plurality of cross dichroic prisms, wherein a repeated half is obtained. 10. A cross for arranging two kinds of dichroic films so as to form a predetermined angle with each other and separating light from a light source into light of three colors of red, green and blue, or making light of three colors incident and combining them. A method for manufacturing a dichroic prism, comprising: forming a bonded body by bonding a first optical member having a flat surface to an optical member having a first dichroic film formed on a flat surface; and a bonding surface of the bonded body. The joined body is cut at a predetermined angle to obtain the first and second joined halves, the cut surfaces of the first and second joined halves are polished, and the first joined half is polished. A second optical member on which a separately prepared second dichroic film is formed is bonded to the polished surface of the body, and a surface of the second optical member opposite to the bonding surface is bonded to a second dichroic film. After removing to the point where the metal is not removed, the first die of the first joint half is removed. The ichroic film surface and the first dichroic film surface of the second bonding half form substantially the same plane,
A method for manufacturing a cross dichroic prism, wherein the first dichroic film and the second dichroic film are arranged so as to form a predetermined angle with each other by bonding the second optical member therebetween.