JP2010039158A - Optical product for projector and method of manufacturing optical product for projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical product for bonding optical members to each other without causing any variation of wavefront aberration or entry of bubbles in a bonding layer, and to provide a method of manufacturing the optical product. <P>SOLUTION: The optical product 6 is used for the projector and is provided with an optical compensation substrate 61 having an optical compensation function, a support substrate 62 for supporting the optical compensation substrate 61, and a bonding layer 63 for molecularly bonding the optical members. The bonding layer 63 is composed of a plasma polymerized film. As a result, the optical compensation substrate 61 and the support substrate 62 are molecularly bonded to dispense with an adhesive, thereby causing no variation in thickness of the bonded part and wavefront aberration while improving light resistance. Furthermore, the optical compensation substrate 61 and the support substrate 62 are molecularly bonded, so that high temperature processing is not required and the bonding is carried out in a short time. The optical compensation substrate 61 and the support substrate 62 are firmly bonded by forming the plasma polymerized film. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical article for a projector having an optical compensation substrate and a manufacturing method thereof.

  For projectors (projection-type liquid crystal display devices) that project light modulated by a liquid crystal panel onto a screen and display an image, liquid crystal is emitted on the exit side of the liquid crystal panel in order not to transmit light from the exit side polarizing plate. There is an optical article that performs optical compensation on molecules (see Patent Document 1). As this optical article, an optical compensation substrate made of quartz or the like and a supporting substrate such as glass bonded can be considered.

  In general, as a conventional example for joining a plurality of optical members, a polarizing plate and a translucent substrate such as sapphire or glass are bonded and fixed with an ultraviolet curable adhesive (see Patent Document 2), silicon and glass, or the like. At the time of bonding, there is a type in which the bonded surfaces are subjected to hydrophilic treatment (activation) with oxygen plasma, the hydrophilic-treated optical members are directly bonded, and heated at about 400 ° C. (see Patent Document 3). Moreover, the method of joining using a silane coupling agent is also proposed (refer patent document 4).

JP 2002-14345 A JP 2008-51998 A Japanese Patent No. 3751972 Japanese Patent No. 2786996

  However, when bonding a thin support substrate with an adhesive used for bonding an optical compensation substrate using the conventional example shown in Patent Document 2, it is difficult to uniformly apply the adhesive in the manufacturing process. There is a problem in that the layer thickness is uneven. Further, when bubbles are mixed in the bonding layer, the thin support substrate is damaged by the operation of removing the bubbles, or the thickness of the bonding layer becomes more uneven. As a result, the substrate surface undulates, causing refraction of the incident / exit oblique light and affecting the image.

Moreover, when the conventional example shown by patent document 3 is used, in conventional solid joining, such as plasma joining, since high temperature of 400 degreeC or more and high pressurization are required, joining by what has a different linear expansion coefficient cannot be performed. In addition, high surface accuracy (parallelism) is required, it is easily affected by atmospheric substance adsorption and foreign matter, and there is a problem that processing in a vacuum is necessary. The method of joining by interposing a solution for dissolving a substrate such as hydrofluoric acid requires time since it is necessary to remove moisture in the solution. Also, sapphire and other materials that are not affected by hydrofluoric acid cannot be joined.
Furthermore, when the silane coupling agent of Patent Document 4 is used, alcohol produced by hydrolysis and water produced by a dehydration reaction are vaporized at the time of heat-curing, and bubbles are formed in the joining layer, or sufficient joining strength is obtained. There are problems such as not being able to get.

  An object of the present invention is to provide an optical article for a projector and an optical article for a projector that do not affect the image projected by the projector and can be joined in a short time even if the optical compensation substrate and the support substrate have different linear expansion coefficients. It is to provide a manufacturing method.

[Application Example 1]
An optical article for a projector according to this application example is an optical article used for a projector that projects light modulated by a liquid crystal panel, and includes an optical compensation substrate having an optical compensation function and a support that supports the optical compensation substrate. A substrate and a bonding layer for molecularly bonding the optical compensation substrate and the support substrate are provided, and the bonding layer is a plasma polymerization film.
In this application example having this configuration, since the optical compensation substrate and the support substrate are molecularly bonded, no adhesive is required. Therefore, in this application example, since no adhesive is used, there is no variation in thickness at the joint between the optical compensation substrate and the support substrate, and wavefront aberration is eliminated. Therefore, there is no inconvenience such as undulation in the image projected by the projector, and a clear image can be projected.
Since the bonding surface of molecular bonding is spontaneously wetted, there is no risk of bubbles entering the bonding layer. In addition, since wettability is high, wetting occurs and joins to the very vicinity of the foreign matter, so that the influence of the foreign matter can be reduced. Furthermore, since the optical compensation substrate and the support substrate are molecularly bonded, it is not necessary to perform processing at a high temperature, and the optical compensation substrate and the support substrate can be bonded in a short time even if the linear expansion coefficients are different.
In addition, plasma polymerized films are formed on the bonding surfaces of the optical compensation substrate and the support substrate, and these polymerized films are pressed together to firmly bond the optical compensation substrate and the support substrate.
Therefore, even if there is a minute uneven surface on the bonding surface between the optical compensation substrate and the support substrate, the uneven surface can be followed by the plasma polymerization film, so that the optical members can be bonded to each other. In addition, even if the optical compensation substrate and the support substrate have different thermal expansion, they can be followed by the plasma polymerization film, so that the image projected by the projector can be easily made clear.

[Application Example 2]
In the optical article for projectors according to this application example, the plasma polymerization film is characterized in that the main material is polyorganosiloxane.
In this application example of this configuration, since the polyorganosiloxane, which is the main material of the plasma polymerized film, is relatively flexible, when joining optical members having different linear expansion coefficients, The stress accompanying expansion can be relaxed. Therefore, peeling of optical members can be reliably prevented. Moreover, since polyorganosiloxane is excellent in chemical resistance, it can be effectively used for optical articles that are exposed to chemicals for a long time. And if the main component of polyorganosiloxane is a polymer of octamethyltrisiloxane, this polymer is not only easy to handle but also a plasma polymerized film made of the polymer has excellent adhesion. Is preferable.

[Application Example 3]
In the optical article for a projector according to this application example, the support substrate is a dust-proof glass or a heat radiating plate.
In this application example having this configuration, since the optical compensation substrate is bonded to the dust-proof glass or the heat radiating plate, the dust-proof glass or the heat radiating plate can also be used as the support substrate. Therefore, it is not necessary to prepare a support substrate as a separate member, the number of parts of the projector can be omitted, and the configuration of the projector can be simplified.

[Application Example 4]
In the optical article for projectors according to this application example, the support substrate is a liquid crystal panel or a prism.
In this application example having this configuration, since the optical compensation substrate can be bonded to the liquid crystal panel or the prism, the liquid crystal panel or the prism can also be used as the support substrate. Therefore, it is not necessary to prepare a support substrate as a separate member, the number of parts of the projector can be omitted, and the configuration of the projector can be simplified.

[Application Example 5]
A method of manufacturing an optical article for a projector according to this application example includes a polymerized film forming step of forming a plasma polymerized film on each of the joint surface of the optical compensation substrate and the joint surface of the support substrate, A surface activation step for activating the plasma polymerization film, and a bonding step for bonding and integrating the optical compensation substrate and the support substrate on which the surface of the plasma polymerization film is activated. It is characterized by that.
In this application example having this configuration, the same operational effects as those of the application example 1 can be obtained.

[Application Example 6]
In the manufacturing method of the optical article for a projector according to this application example, the bonding step is an arrangement step in which one end of the optical compensation substrate and the support substrate are overlapped and the other ends are separated from each other. And a pressing step in which the optical compensation substrate is bonded to the support substrate while being bent by being pressed against the curved surface continuously from the one end to the other end by a pressing member having a roller-shaped curved surface. It is characterized by having.
In this application example having this configuration, since the pressing member continuously bonds, there is no possibility that bubbles may enter the bonding layer. For this reason, since it can join in air | atmosphere, not in a vacuum, a vacuum device can be abbreviate | omitted and the manufacturing cost of a projector can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows an example of a projector using an optical article according to an embodiment of the present invention.
As shown in FIG. 1, the projector 1 includes an exterior housing 2, a projection lens 3 as a projection optical device, an optical unit 4, and the like.

The optical unit 4 includes a light source device 41, a uniform illumination optical device 42, a color separation optical device 43, a relay optical device 44, an optical device 45, and an optical component that houses and arranges these optical components 42 to 45 therein. And a housing 46.
The light source device 41 includes a light source lamp 411, a reflector 412, and a collimating lens 413. The radial light beam emitted from the light source lamp 411 is reflected by the reflector 412 and passes through the collimating lens 413. Ejected as parallel light.

The uniform illumination optical device 42 includes a first lens array 421, a second lens array 422, a polarization conversion element 423, and a superimposing lens 424.
The first lens array 421 has a configuration in which first small lenses having a substantially rectangular outline when viewed from the incident optical axis direction are arranged in a matrix in a plane substantially orthogonal to the incident optical axis. . Each first small lens splits the light beam emitted from the light source device 41 into a plurality of partial light beams.

The second lens array 422 has substantially the same configuration as the first lens array 421, and has a configuration in which the second small lenses are arranged in a matrix. The second lens array 422 has a function of forming an image of each first small lens of the first lens array 421 on a liquid crystal panel (to be described later) of the optical device 45 together with the superimposing lens 424.
A polarization conversion element 423 is installed between the second lens array 422 and the superimposing lens 424.

The color separation optical device 43 includes two dichroic mirrors 431 and 432 and a reflection mirror 433, and a plurality of partial light beams emitted from the uniform illumination optical device 42 by the dichroic mirrors 431 and 432 are converted into red, green, and blue. It has a function of separating into three color lights.
The relay optical device 44 includes an incident side lens 441, a relay lens 443, and reflection mirrors 442 and 444, and guides the red light separated by the color separation optical device 43 to a later-described red light liquid crystal panel of the optical device 45. It has a function.

  At this time, the dichroic mirror 431 of the color separation optical device 43 reflects the blue light component of the light beam emitted from the uniform illumination optical device 42 and transmits the red light component and the green light component. The blue light reflected by the dichroic mirror 431 is reflected by the reflection mirror 433, passes through the field lens 425, and reaches a later-described blue light liquid crystal panel of the optical device 45.

  The field lens 425 converts each partial light beam emitted from the second lens array 422 into a light beam parallel to the central axis (principal ray). The same applies to the field lens 425 provided on the light beam incident side of the other liquid crystal panel for green light and red light.

Of the red light and green light transmitted through the dichroic mirror 431, the green light is reflected by the dichroic mirror 432, passes through the field lens 425, and reaches a later-described green light liquid crystal panel of the optical device 45.
On the other hand, the red light passes through the dichroic mirror 432, passes through the relay optical device 44, passes through the field lens 425, and reaches a later-described red light liquid crystal panel of the optical device 45.

  The optical device 45 includes three liquid crystal panels 451 as light modulation devices (the liquid crystal panel for red light is 451R, the liquid crystal panel for green light is 451G, and the liquid crystal panel for blue light is 451B), and these liquid crystals The polarizing element 5 is disposed on each of the light incident side and the light emitting side of the panel 451, the optical article 6 of the present embodiment disposed between the liquid crystal panel 451 and the polarizing element 5, and a cross dichroic prism 454. .

  The cross dichroic prism 454 forms a color image by synthesizing the optical image modulated for each color light emitted from the emission side polarizing plate 5B. The color image formed by the cross dichroic prism 454 is enlarged and projected onto a screen or the like by the projection lens 3 described above.

FIG. 2 is a schematic configuration diagram of the optical article. In FIG. 2, an optical article 6 is provided to improve the contrast of the projector, and includes an optical compensation substrate 61, a support substrate 62 that supports the optical compensation substrate 61, and the support substrate 62 and the optical compensation substrate 61. And a bonding layer 63 for molecular bonding. Further, the optical compensation substrate 61 and the support substrate 62 have different linear expansion coefficients.
Here, the optical compensation substrate 61 is a thin plate formed of quartz, sapphire, or other material having birefringence, and the support substrate 62 is a glass plate that holds the thin wavelength plate.
Examples of the crystal material for forming the optical compensation substrate 61 include LiNbO ₃ (lithium niobate), sapphire, BBO, calcite, YVO _{4 and the} like in addition to quartz. And as a material which forms the support substrate 62, optical glass, such as quartz glass, borosilicate glass, crystallized glass, can be illustrated, for example. Here, the support substrate 62 may also serve as dust-proof glass or a heat sink. In FIG. 2A, the support substrate 62 is provided separately, but also serves as a liquid crystal panel 451 as shown in FIG. 2B and serves as a cross dichroic prism 454 as shown in FIG. Also good.

  In the present embodiment, the bonding layer 63 is formed of a plasma polymerization film. In the figure, the thickness of the bonding layer 63 is shown to be thicker than the thickness of the optical compensation substrate 61 and the support substrate 62 in order to facilitate understanding of the contents.

A process for forming the bonding layer 63 with a plasma polymerization film will be described.
A plasma polymerization film 631 is provided on each of the bonding surface of the optical compensation substrate 61 and the bonding surface of the support substrate 62, and these plasma polymerization films 631 are polymerized to form a bonding layer 63 (see FIG. 5). ).
As will be described later, the main material of the plasma polymerized film 631 used in the present embodiment is polyorganosiloxane. This polyorganosiloxane is a general term for polymer compounds having a siloxane bond.

A method for manufacturing the optical article 6 in which the bonding layer 63 is formed of a plasma polymerized film will be described with reference to FIGS.
FIG. 3 is a schematic view of a plasma polymerization apparatus used in this embodiment.
In FIG. 3, the plasma polymerization apparatus 100 includes a chamber 101, a first electrode 111 and a second electrode 112 provided inside the chamber 101, and a high frequency between the first electrode 111 and the second electrode 112. The power supply circuit 120 applies a voltage, the gas supply unit 140 supplies gas into the chamber 101, and the exhaust pump 150 discharges the gas inside the chamber 101.
The first electrode 111 supports the optical compensation substrate 61 and the support substrate 62 as a base material, and the first electrode 111 and the second electrode 112 are arranged to face each other with the optical compensation substrate 61 and the support substrate 62 interposed therebetween. ing.

The power supply circuit 120 includes a matching box 121 and a high frequency power supply 122.
The gas supply unit 140 includes a liquid storage unit 141 that stores a liquid film material (raw material liquid), a vaporizer 142 that vaporizes the liquid film material and changes it into a raw material gas, and a gas cylinder 143 that stores a carrier gas. I have. The carrier gas stored in the gas cylinder 143 is a gas that is discharged by the action of an electric field and is introduced into the chamber 101 in order to maintain this discharge, and corresponds to, for example, argon gas or helium gas.
The liquid storage unit 141, the vaporizer 142, the gas cylinder 143, and the chamber 101 are connected by a pipe 102, and the mixed gas of the gaseous film material and the carrier gas is supplied into the chamber 101. ing.
The film material stored in the liquid storage unit 141 is a raw material for forming the plasma polymerization film 631 on the optical compensation substrate 61 and the support substrate 62 by the plasma polymerization apparatus 100 and is vaporized by the vaporization apparatus 142 to become a raw material gas. .

Examples of the source gas include methylsiloxane, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, and methylphenylsiloxane. Examples include gallium, trimethylaluminum, triethylaluminum, triisobutylaluminum, trimethylindium, triethylindium, trimethylzinc, triethylzinc, organometallic compounds, various hydrocarbon compounds, various fluorine compounds, and the like.
The plasma polymerized film 631 obtained by using such a raw material gas is formed by polymerizing these raw materials (polymer), that is, polyorganosiloxane, organometallic polymer, hydrocarbon polymer, fluorine polymer, or the like. Will be composed.

The surface of the polyorganosiloxane usually exhibits water repellency, but the organic group can be easily removed by applying various activation treatments, and can be changed to hydrophilic. That is, polyorganosiloxane is a material that can easily control water repellency and hydrophilicity.
Even if the plasma polymerized films 631 made of polyorganosiloxane exhibiting water repellency are brought into contact with each other, the adhesion is hindered by the organic group, and it is extremely difficult to adhere. On the other hand, plasma polymerized films 631 made of polyorganosiloxane exhibiting hydrophilicity can be bonded particularly easily when they are brought into contact with each other. That is, the advantage that the water repellency and hydrophilicity can be easily controlled leads to the advantage that the adhesiveness can be easily controlled. Therefore, the plasma polymerized film 631 made of polyorganosiloxane is preferably used in this embodiment. Will be used. Since the polyorganosiloxane is relatively flexible, even if the constituent materials of the optical compensation substrate 61 and the support substrate 62 are different and the coefficients of linear expansion are different, the optical compensation substrate 61 and the support substrate 62 are different. It is possible to relieve stress accompanying thermal expansion that occurs between them. Furthermore, since polyorganosiloxane is excellent in chemical resistance, it can be effectively used for joining members that are exposed to chemicals for a long period of time.

  Among the polyorganosiloxanes, those mainly composed of a polymer of octamethyltrisiloxane are preferred. Since the plasma polymerized film 631 mainly composed of a polymer of octamethyltrisiloxane is excellent in adhesiveness, it is preferably used in the bonding method of this embodiment. The polymer of octamethyltrisiloxane is easy to handle because it has moderate fluidity at room temperature.

Next, the procedure of the method for manufacturing the optical article 6 in which the bonding layer 63 is formed from the plasma polymerized film 631 will be described with reference to FIGS.
First, as shown in FIGS. 4A to 4D, a plasma polymerization film 631 is formed on the bonding surface of the optical compensation substrate 61 and the support substrate 62 (polymerization film forming step).
In this polymerization film forming step, the optical compensation substrate 61 or the support substrate 62 is held as a base material on the first electrode 111 of the chamber 101 of the plasma polymerization apparatus 100. Then, a predetermined amount of oxygen is introduced into the chamber 101 and a high frequency voltage is applied from the power supply circuit 120 between the first electrode 111 and the second electrode 112 to clean the surface and activate the optical member itself (substrate) Activation).
Thereafter, when the gas supply unit 140 is operated, a mixed gas of the source gas and the carrier gas is supplied into the chamber 101. The supplied mixed gas is filled into the chamber 101, and as shown in FIG. 4A, the mixed gas is exposed to the optical compensation substrate 61 or the support substrate 62 as a base material.

The ratio (mixing ratio) of the raw material gas in the mixed gas is slightly different depending on the kind of the raw material gas and the carrier gas, the target film forming speed, and the like. It is preferable to set, and it is more preferable to set to about 30 to 60%.
The frequency applied between the first electrode 111 and the second electrode 112 is not particularly limited, but is preferably about 1 kHz to 100 MHz, and more preferably about 10 to 60 MHz. But not limited high frequency power density, in particular, it is preferably about 0.1mW~10W / cm ^2, more preferably about 1mW~1W / cm ^2.

The pressure of the chamber 101 at the time of film formation is preferably about 133.3 × 10 ^{−5 to} 133.3 Pa (1 × 10 ^{−5 to} 10 Torr), preferably 133.3 × 10 ^{−4 to} 133.3 Pa (1 It is more preferable that it is about × 10 ^{−4 to 1} Torr).
The raw material gas flow rate is preferably about 0.5 to 200 sccm, more preferably about 1 to 100 sccm.
The carrier gas flow rate is preferably about 5 to 750 sccm, more preferably about 10 to 100 sccm.
The treatment time is preferably about 1 to 10 minutes, more preferably about 4 to 7 minutes.
The temperature of the optical compensation substrate 61 or the support substrate 62 as a base material is preferably 25 ° C. or higher, and more preferably 25 to 100 ° C.

By applying a high-frequency voltage between the first electrode 111 and the second electrode 112, gas molecules existing between the electrodes 111 and 112 are ionized, and plasma is generated. The molecules of the source gas are polymerized by the energy of the plasma, and the polymer is adhered and deposited on the surface of the optical compensation substrate 61 or the support substrate 62 as shown in FIG. As a result, a plasma polymerization film 631 is formed on the bonding surface of the optical compensation substrate 61 or the support substrate 62 as shown in FIG.
The average thickness of the plasma polymerized film 631 is 10 to 1000 nm, and preferably 50 to 500 nm. If the average thickness of the plasma polymerized film 631 is less than 10 nm, sufficient bonding strength cannot be obtained, and if it exceeds 1000 nm, the film formation time becomes long and the productivity is lowered.

Thereafter, as shown in FIG. 4D, the plasma polymerization film 631 is activated to activate the surface (surface activation step).
For the surface activation step, for example, a method of irradiating plasma, a method of contacting with ozone gas, a method of treating with ozone water, a method of treating with alkali, or the like can be used.
Here, the term “activate” means a state in which molecular bonds inside the plasma polymerized film 631 and the inside thereof are cleaved and unterminated bonds are formed, or OH groups are bonded to the cleaved bonds. A state or a state in which these states are mixed.
In this surface activation step, a method of irradiating plasma is preferable in order to efficiently activate the surface of the plasma polymerized film 631. The reason for irradiating the surface of the plasma polymerized film 631 is that the molecular structure of the plasma polymerized film 631 is not cut more than necessary, for example, until the boundary between the plasma polymerized film 631 and the optical compensation substrate 61 or the support substrate 62 is reached. This is for avoiding deterioration of the characteristics of the plasma polymerized film 631. Moreover, you may perform a surface activation process and a polymeric film formation process continuously as a series of processes.

As the plasma used in the present embodiment, for example, oxygen, argon, nitrogen, air, water, or the like can be used alone or in combination. Among these, it is preferable to use oxygen.
By using such plasma, it is possible to prevent a significant deterioration in the characteristics of the plasma polymerized film 631 and to eliminate unevenness in a wide range and to perform processing in a shorter time. And since plasma can be generated with the same equipment as the apparatus for forming the plasma polymerized film, there is also an advantage that the manufacturing cost can be reduced.
The time for irradiating the plasma is not particularly limited as long as the molecular bond in the vicinity of the surface of the plasma polymerized film 631 can be broken, but it is preferably about 5 to 30 minutes, and 10 to 60 seconds. More preferred.
Bonds that are not terminated due to cleavage of the surface and internal molecular bonds are introduced into the surface of the plasma polymerized film 631 activated in this way, and a part of the broken bonds is also introduced. OH groups are introduced.
In this embodiment, a step of cleaning the optical compensation substrate 61 and the support substrate 62 may be provided between the plasma polymerization film forming step and the surface activation step. This cleaning step is performed using chemicals, water, or other appropriate means.

The optical compensation substrate 61 and the support substrate 62 on which the surface of the plasma polymerization film 631 is activated are bonded and integrated (bonding step).
At this time, as shown in FIG. 5 (A), the optical compensation substrate 61 and the support substrate 62 are overlapped with each other in a state where the plasma polymerization films 631 are opposed to each other, and the other ends are separated from each other. Arrange so that. In order to separate the other end, an engaging member 8 having both ends engaged with the other end of the optical compensation substrate 61 and the base 7 is provided. One end of the engaging member 8 engaged with the base 7 is engaged with the base 7 so as to be slidable in the horizontal direction. As a result, the engagement member 8 slides on the base 7 so that the separation distance of the other end of the optical compensation substrate 61 and the support substrate 62 can be freely adjusted, and the other end is separated or abutted. ing.

Next, as shown in FIG. 5B, the pressing member 9 includes a shaft portion 91 serving as a rotation shaft and a semi-elliptical cylindrical body 92 having a roller-shaped curved surface that comes into contact with the optical compensation substrate 61. Yes. Then, the semi-elliptical cylinder 92 is disposed so as to contact the optical compensation substrate 61 on the opposite side to the plasma polymerization film 631. At this time, the contact portion between the semi-elliptical cylinder 92 and the optical compensation substrate 61 coincides with one end where the optical compensation substrate 61 and the support substrate 62 overlap each other.
As shown in FIG. 5C, the pressing member 9 is optically pressed by pressing the semi-elliptical cylinder 92 around the shaft portion 91 in order from the one end to the other end while rotating on the optical compensation substrate 61. The plasma polymerized film 631 of the compensation substrate 61 and the support substrate 62 is joined in order from one end to the other end to form the joining layer 63. At this time, when the optical compensation substrate 61 is pressed, one end of the engagement member 8 slides on the base 7 as the separation distance decreases. Further, since the engaging member 8 slides when a predetermined force or more is applied, the thin optical compensation substrate 61 is slightly bent when pressed against the semi-elliptical cylinder. For this reason, it is possible to prevent entrainment of bubbles in the bonding layer 63.

Then, as shown in FIG. 5D, the semi-elliptical cylinder 92 rotates to the other end of the optical compensation substrate 61, and the engaging member 8 is detached from the other end, and the optical compensation substrate 61 and the support substrate 62 Are bonded together via the bonding layer 63.
In addition, since the activated state of the plasma polymerized film 631 whose surface has been activated relaxes with time, the plasma polymerized film 631 moves to the bonding step immediately after the surface activation step. Specifically, after the surface activation step, it is preferable to shift to the pasting step within 60 minutes, and it is more preferable to shift within 5 minutes. Within this time, since the surface of the plasma polymerized film 631 maintains a sufficient active state, sufficient bonding strength can be obtained at the time of bonding.

By bonding the plasma polymerized films 631 to each other, these films are bonded to each other. This coupling | bonding is estimated based on the following (1) or (2) or the mechanism of (1) and (2).
(1) Two substrates, in this embodiment, when the optical compensation substrate 61 and the support substrate 62 are bonded together, OH groups present on the surface of each plasma polymerization film 631 are adjacent to each other. The adjacent OH groups attract each other by hydrogen bonding, and an attractive force is generated between the OH groups. In addition, OH groups attracting each other by this hydrogen bond are detached from the surface with dehydration condensation depending on temperature conditions. As a result, at the contact boundary between the two plasma polymerized films 631, the bonds where the detached OH groups are bonded are bonded. That is, the respective base materials constituting each plasma polymerized film 631 are directly coupled and integrated to form one plasma polymerized film, that is, the bonding layer 63.
(2) When two base materials are bonded together, unterminated bonds generated on the surface and inside of each plasma polymerization film 631 are recombined. Since this recombination occurs in a complicated manner so as to overlap (entangle) with each other, a network-like bond is formed at the bonding interface. As a result, the respective base materials constituting each plasma polymerized film 631 are directly joined and integrated to form one plasma polymerized film, that is, the joining layer 63.

  Moreover, you may pressurize the optical compensation board | substrate 61 and the support substrate 62 as needed after a bonding process. In this pressurization, it is preferable to pressurize the optical compensation substrate 61 and the support substrate 62 with a large force in order to increase the bonding strength. Specifically, the pressure for pressurization is preferably about 1 to 10 MPa, more preferably 1 to 5 MPa, although it varies depending on the thickness dimensions of the optical compensation substrate 61 and the support substrate 62 and the conditions of the apparatus and the like. The pressurization time is not particularly limited, but is preferably about 10 sec to 30 min.

  In this embodiment, since the non-activated polymer film is chemically stable, a large number of optical compensation substrates 61 and support substrates 62 each having a plasma polymer film 631 formed thereon are manufactured in the polymer film formation step. Set it aside. And finally, only the required number passes through a surface activation process, activates the plasma polymerization film 631, and promptly moves to the bonding process, whereby the manufacturing efficiency of the optical article 6 can be improved.

In the present embodiment having the above-described configuration, the following operational effects can be achieved.
(1) An optical article 6 used in the projector 1, which is an optical compensation substrate 61 having an optical compensation function, a support substrate 62 that supports the optical compensation substrate 61, and a bonding layer 63 that molecularly bonds these optical members. The bonding layer 63 is a plasma polymerized film 631.
Therefore, since the optical compensation substrate 61 and the support substrate 62 are molecularly bonded, no adhesive is required. Therefore, since no adhesive is used, there is no variation in thickness at the joint between the optical compensation substrate 61 and the support substrate 62, there is no wavefront aberration, and light resistance is improved.
Since the bonding surface of the molecular bonding is spontaneously wetted, there is no possibility of bubbles entering the bonding layer 63. In addition, since wettability is high, wetting occurs and joins to the very vicinity of the foreign matter, so that the influence of the foreign matter can be reduced. Furthermore, since the optical compensation substrate 61 and the support substrate 62 are molecularly bonded, processing at a high temperature is not necessary and bonding can be performed in a short time.
In addition, plasma polymerization films 631 are formed on the bonding surfaces of the optical compensation substrate 61 and the support substrate 62, respectively, and these plasma polymerization films 631 are pressed together to firmly bond the optical compensation substrate 61 and the support substrate 62 together.
Therefore, even if there is a minute uneven surface on the bonding surface between the optical compensation substrate 61 and the support substrate 62, the uneven surface can be followed by the plasma polymerization film 631, so that the optical members can be bonded to each other. In addition, even if the optical compensation substrate 61 and the support substrate 62 have different thermal expansion, the plasma polymerization film 631 can follow them.

(2) Since the support substrate 62 is a dust-proof glass or a heat radiating plate, the optical compensation substrate 61 is directly joined to the dust-proof glass or the heat radiating plate, so that the dust proof glass or the heat radiating plate can be used as the support substrate 62. Therefore, it is not necessary to prepare the support substrate 62 as a separate member, the number of parts of the projector 1 can be omitted, and the configuration of the projector 1 can be simplified.

(3) Since the support substrate 62 is a liquid crystal panel or prism, the optical compensation substrate 61 can be directly bonded to the liquid crystal panel or prism, so that the liquid crystal panel or prism can also be used as the support substrate 62. Therefore, it is not necessary to prepare the support substrate 62 as a separate member, the number of parts of the projector 1 can be omitted, and the configuration of the projector 1 can be simplified.

(4) The manufacturing method of the optical article 6 includes a polymerization film forming step of forming a plasma polymerization film 631 on each of the bonding surface of the optical compensation substrate 61 and the bonding surface of the support substrate 62, and plasma polymerization formed on the bonding surface. A surface activation step for activating the film 631 and a bonding step for bonding and integrating the optical compensation substrate 61 and the support substrate 62 in which the surface of the plasma polymerization film 631 is activated are combined. . For this reason, there can exist an effect similar to said (1).

(5) In the manufacturing method of the optical article 6, the bonding step includes an arrangement step in which one end of the optical compensation substrate 61 and the support substrate 62 are overlapped and the other ends are separated, and a roller shape. And a pressing step in which the optical compensation substrate 61 is bonded to the support substrate 62 while being bent by being pressed against the curved surface continuously from one end to the other end by the pressing member 9 having the curved surface. To do.
For this reason, since it sticks continuously by the press member 9, there is no possibility that a bubble may enter into the joining layer 63. FIG. Therefore, since it is not necessary to be in a vacuum and bonding can be performed in the atmosphere, a vacuum apparatus can be omitted, and the manufacturing cost can be reduced.

Hereinafter, examples will be described in order to confirm the effects of the present embodiment.
The embodiment corresponds to the optical article 6 configured by bonding the optical compensation substrate 61 and the support substrate 62 through the plasma polymerization film 631. A quartz substrate having a vertical and horizontal thickness dimension of 25 mm × 22 mm × 10 μm was used as the optical compensation substrate 61, and a quartz substrate having a vertical and horizontal thickness dimension of 25 mm × 22 mm × 0.5 mm was used as the support substrate 62.
[Plasma polymerized film forming process]
In the embodiment, a substrate corresponding to the optical compensation substrate 61 and the support substrate 62 is put into the chamber 101 of the plasma polymerization apparatus 100, 100 ccm of oxygen is introduced into the chamber 101, and the first electrode 111 provided inside the chamber 101. The substrate is activated by supplying a voltage of 13.5 MHz and a power of 100 W between the first electrode 112 and the second electrode 112. The time is 60 seconds.
Thereafter, a raw material gas and a carrier gas are introduced into the chamber 101 under the following film forming conditions to form a plasma polymerization film.
<Film formation conditions>
Source gas composition: Octamethyltrisiloxane Source gas flow rate: 10 sccm
Carrier gas composition: Argon Carrier gas flow rate: 10 sccm
High frequency power output: 100W
Processing time: 10 minutes Film thickness: 350 nm

[Surface activation process]
The plasma polymerization film 631 is irradiated with ultraviolet rays under the following conditions to activate the surface. <Plasma irradiation conditions>
Introduced gas: Oxygen Flow rate: 20sccm
Degree of vacuum: 55 Pa
Applied voltage: 100 W (frequency 13.56 MHz)
Irradiation time: 30 sec
In this embodiment, the substrate is cleaned between the plasma polymerization film forming step and the surface activation step.

[Bonding process]
A pair of substrates on which the plasma polymerized films 631 are formed are bonded together with the plasma polymerized films 631 facing each other.
[Pressure process]
Further, the pair of substrates is pressurized using an atmospheric pressure press. The pressurizing condition at this time is 10 kN, 10 seconds, and the temperature is room temperature (20 ° C.).

[Comparative example]
In the comparative example, a photocurable adhesive (trade name UT20) is applied to the bonding surfaces of the pair of substrates, and these substrates are bonded together, and then irradiated with 200 mJ / cm ² (365 nm) of ultraviolet rays. It has been cured. The in-plane distribution of the thickness of the joint formed by this photo-curing adhesive is approximately 5 μm to 10 μm.

The wavefront measurement was performed using the measuring device (trade name: FUJINON interferometer; λ = 632.8 nm) for the example and the comparative example created under the above conditions. FIG. 6 is a schematic diagram of the measuring apparatus. In FIG. 6, light irradiated from a light source (not shown) is projected onto the screen S through the incident side polarizing plate 5A, the liquid crystal panel 451, the optical article 6, the emission side polarizing plate 5B, and the lens L. As a result, although the transmitted wavefront aberration was small in the example, it can be understood from FIGS. 7 and 8 that the transmitted wavefront aberration is large in the comparative example.
FIG. 7 shows the result of measuring the transmitted wavefront aberration with the above-mentioned measuring instrument when the example is prepared. FIG. 8 shows the result of measuring the transmitted wavefront aberration with the measuring instrument when a comparative example is created.
As shown in FIG. 7, it can be seen that in the example, the interference fringes cannot be recognized and the wavefront aberration is extremely low. On the other hand, as shown in FIG. 8, in the comparative example, the interference fringes can be clearly recognized, so that the wavefront aberration is extremely high.
By adopting a bonding method in which the film thickness of the bonding portion is thin in this way, the in-plane film thickness distribution is improved, and thus the optical article 6 with extremely low wavefront aberration can be obtained.

The result of the projection image projected by the projector 1 using the optical article 6 obtained in the example and the comparative example will be described based on FIGS. 9 to 11. FIG. 9 is a diagram illustrating an extraction portion of a projection image projected by a projector using the optical article of the example and the comparative example. FIG. 10 is a diagram illustrating a projection image projected by the projector according to the embodiment. FIG. 11 is a diagram illustrating a projection image projected by the projector of the comparative example.
As shown in FIGS. 9 to 11, the projected image 10 projected from the projector is projected on a screen (not shown). This projection image is a cross-hatch image having a length of 800 mm and a width of 1000 mm, and two extracted images A and B of 150 mm in length and width extracted from the vicinity of the edge (A) and the center (B) of the cross-hatch image. These are extracted images of the respective projection images in the example and the comparative example as shown in FIGS.
From FIG. 10, it can be seen that the extracted images A and B in the embodiment are clearly projected with a cross hatch. On the other hand, it can be seen from FIG. 11 that the extracted images A and B in the comparative example are unclear in the cross hatch and are blurred in the cross hatch. By adopting a bonding method in which the film thickness of the bonding portion is thin like the optical article 6 of the embodiment, the optical article 6 having extremely low wavefront aberration can be obtained, and by using this, an extremely clear projection image 10 can be obtained. The obtained projector 1 can be obtained.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the above-described embodiment, the bonding layer 63 is formed between one optical compensation substrate 61 and one support substrate 62. However, in the present invention, at least the optical compensation substrate 61 and the support substrate 62 are not separated. One may be divided into a plurality, and three or more optical members may be bonded to each other via a bonding layer.
The optical compensation substrate 61 is joined to the support substrate 62. However, the present invention is not limited to this, and the optical compensation substrate 61 may be joined to any one of dustproof glass, a heat radiating plate, a liquid crystal panel, and a prism. Thereby, there is no need to use another support substrate 62, the number of parts can be reduced, and the configuration of the projector 1 can be simplified.
In the above embodiment, one optical article 6 is used, but the present invention is not limited to this. For example, two optical compensation substrates 61 and two support substrates 62 may be bonded to each other to form two optical articles 6, or the two optical compensation substrates 61 may each be a dustproof glass, a heat radiating plate, and a liquid crystal panel. And may be joined to either of the prisms.
In the above-described embodiment, the optical compensation substrate 61 and the support substrate 62 are sequentially overlapped and joined from one end to the other by the pressing member, but the present invention is not limited thereto. For example, the optical compensation substrate 61 and the support substrate 62 may be pressed and joined to each other in a state of facing the substantially parallel substrate.

  The present invention can be used for an optical article used in a projector.

Schematic which shows an example of the projector using the optical article of embodiment of this invention. The schematic block diagram in the case of explaining the wave plate with a glass plate as an optical article of embodiment of this invention. Schematic of the plasma polymerization apparatus used in this embodiment. Schematic explaining the procedure of the manufacturing method of the optical article in which a joining layer is formed from a plasma polymerization film. Schematic explaining the procedure of the manufacturing method of the optical article in which a joining layer is formed from a plasma polymerization film. Schematic of a measuring device. The figure which shows the result of having measured the transmitted wavefront aberration of the Example. The figure which shows the result of having measured the transmitted wavefront aberration of the comparative example. The figure which shows the extraction part of the cross hatch which the projector of the Example and the comparative example projected. The figure which shows the cross hatch which the projector of the Example projected. The figure which shows the cross hatch which the projector of the comparative example projected.

Explanation of symbols

  6 ... Optical article, 61 ... Optical compensation substrate, 62 ... Support substrate, 63 ... Bonding layer, 631 ... Plasma polymerized film

Claims (6)

An optical article for a projector used for a projector that projects light modulated by a liquid crystal panel,
An optical compensation substrate having an optical compensation function, a support substrate that supports the optical compensation substrate, and a bonding layer that molecularly bonds the optical compensation substrate and the support substrate, and the bonding layer is a plasma polymerization film. An optical article for a projector characterized by the above. The optical article for a projector according to claim 1,
The plasma polymerized film is an optical article for projectors characterized in that a main material thereof is polyorganosiloxane. In the optical article for projectors according to claim 1 or 2,
An optical article for a projector, wherein the support substrate is dust-proof glass or a heat sink. In the optical article for projectors according to claim 1 or 2,
An optical article for a projector, wherein the support substrate is a liquid crystal panel or a prism. A method for producing an optical article for a projector according to any one of claims 1 to 4,
A polymerized film forming step of forming a plasma polymerized film on each of the bonded surface of the optical compensation substrate and the bonded surface of the support substrate;
A surface activation step for activating the plasma polymerization film formed on the bonding surface;
A bonding step of bonding and integrating the optical compensation substrate whose surface of the plasma polymerized film is activated and the support substrate; and a method for producing an optical article for a projector. In the manufacturing method of the optical article for projectors described in Claim 5,
The bonding step is an arrangement step in which one end of the optical compensation substrate and the support substrate are overlapped and the other ends are separated from each other, and
A pressing step in which the optical compensation substrate is bonded to the support substrate while being bent by being pressed against the curved surface continuously from the one end to the other end by a pressing member having a roller-shaped curved surface. A method of manufacturing an optical article for a projector, characterized in that: