JPH0519106A - Laminated color lens - Google Patents

Abstract

PURPOSE:To efficiently produce a laminated color lens having a uniform characteristic and with the change of the filter characteristic reduced by a specified process by coloring an adhesive layer with a light absorbing substrate. CONSTITUTION:A concave lens 1 and a convex lens 2 are laminated through an adhesive layer 3 with the flat contact surface 11 formed on the peripheral end of the lens 1 opposed to the flat contact surface 21 formed on the peripheral end of the concave lens 2. A substrate having a desired light absorptivity is selected from various dyes and pigments and used as the light absorbing substance to be incorporated into the adhesive layer 3, and the copper phthalocyanins capable of absorbing light having about 600nm wavelength and excellent in light resistance is preferably used in the case of the laminated color lens to be used for the green projection tube of a projection color television.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated color lens, and more specifically, it has an advantage that it has uniform filter characteristics and little change in filter characteristics, and that it can be efficiently manufactured by a simplified process. Have
For example, the present invention relates to a laminated color lens suitably used for a projection television projection device.

[0002]

2. Description of the Related Art For example, in a projection television, a colored lens may be used for the purpose of blocking undesirably generated unnecessary wavelength light due to the characteristics of a projection tube.

The colored lens is usually a single glass lens or a plurality of glass lenses having different refractive indexes and at least one of which is colored, which are bonded together via an adhesive layer. On the other hand, a cemented lens in which plastic lenses are cemented together is significantly lighter than a glass lens in which glass lenses are cemented together, and the degree of freedom in molding each lens is great. Since glass has the advantage that it is easy to use an aspherical lens, which is extremely difficult to manufacture with glass, the demand for it has expanded in recent years.

Therefore, as a bonded color lens in which a plurality of plastic lenses, at least one of which is colored, are bonded with an adhesive, a structure as shown in FIG. 4 can be considered. That is, in FIG. 4, reference numeral 101 denotes a concave lens made of polycarbonate (PC), for example.
On the other hand, a convex lens 102 made of an acrylic resin in which a dye or a pigment is kneaded is attached via an adhesive layer 103.

[0005]

However, in the laminated color lens shown in FIG. 4, since the lens itself is colored, the thickness of the lens is not uniform in the central portion and the outer peripheral portion. As a result, there is a difference in the filter characteristics between the portions through which the light rays pass, and there is a problem that the change in the filter characteristics is large.

Further, R (red), G (green) and B
When attaching a laminated color lens to at least one of the three (blue) tubes, a colored lens in the one tube and another lens of another color such as uncolored are required.
There is also a problem that the mold and the molding machine need to be washed after each lens molding setup, resulting in poor production efficiency.

The present invention has been made based on the above-mentioned circumstances, and an object of the present invention is to have uniform filter characteristics with little change in filter characteristics, and to efficiently manufacture in a simplified process. It is to provide a possible laminated color lens.

[0008]

The bonded color lens of the present invention made to achieve the above object is a bonded color lens in which a plurality of lenses are bonded via an adhesive layer. The adhesive layer is characterized in that it is colored with a light absorbing substance that absorbs light of a specific wavelength.

[0009]

In the laminated color lens of the present invention, the adhesive layer interposed between the lenses is colored with a light absorbing substance that absorbs light of a specific wavelength, so that filter characteristics are imparted. Here, the thickness uniformity of the adhesive layer is far better than the thickness uniformity of the lens, and since the thickness of the adhesive layer can be made almost uniform, the filter characteristics are also almost uniform. Therefore, there is little change in the filter characteristics. Moreover, since the coloring of the lens itself is unnecessary,
It is not necessary to prepare lenses of different colors when manufacturing laminated color lenses of different colors, and therefore cleaning of the mold and molding machine at the time of lens molding is not required, and the process is simplified and efficient. Manufactured.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan sectional view showing an outline of an example of a laminated color lens of the present invention.

As shown in FIG. 1, in this bonded color lens, a concave lens 1 and a convex lens 2 are bonded together via an adhesive layer 3. The material for forming the concave lens 1 and the convex lens 2 may be either optical glass or plastic, as long as it is a combination of materials having different refractive indices, but plastic is preferable,
Among plastics, polycarbonate (PC) resin, polystyrene (PS) resin, styrene-acrylonitrile copolymer (MS) resin, polymethylmethacrylate (PMMA) resin, polydiethylene glycol bisallyl carbonate (PEDC) resin, poly-4-methylpentene-1 (TPX) resin is particularly preferred.

More specifically, polycarbonate (P
C) The concave lens 1 is formed of a plastic having a high optical dispersity such as a resin and a polystyrene (PS) resin, and a polymethyl methacrylate (PMMA) resin and a polydiethylene glycol bisallyl carbonate (PED) are used.
It is preferable to form the convex lens 2 with a plastic having a low optical dispersion such as C) resin and poly-4-methylpentene-1 (TPX) resin. The styrene-acrylonitrile copolymer (MS) resin is polystyrene (PS)
It can be used on both the high dispersion side and the low dispersion side by changing the mixing ratio of the resin and the polymethylmethacrylate (PMMA) resin.

In this embodiment, the concave lens 1 is made of polycarbonate (PC) resin and the convex lens 2 is made of polymethylmethacrylate (PMMA) resin. Here, the refractive index of the concave lens 1 made of polycarbonate resin (PC) is about 1.53, and the refractive index of the convex lens 2 made of polymethylmethacrylate (PMMA) resin is about 1.49. Such a laminated color lens including a combination of the concave lens 1 and the convex lens 2 can be suitably used especially for a projection device of a production television.

The concave lens 1 and the convex lens 2 are, for example, as shown in FIG. 1, a flat contact surface 11 formed on the peripheral end of the concave lens 1 and a flat contact surface 11 formed on the peripheral end of the convex lens 2. With the contact surface 21 facing each other, the adhesive layer 3
It may be pasted together via a sheet or, as shown in FIG.
As shown in FIG. 1, for example, a positioning flange 12 is provided on the peripheral end of the concave lens 1, and the concave lens 1 and the convex lens 2 are in contact with the positioning flange 12 with the engaging portion 22 formed on the peripheral end of the convex lens 2. Alternatively, the adhesive layer 3 may be interposed between both lenses. Here, in the case of the latter configuration, for example, as shown in FIG. 2, an adhesive reservoir 13 for releasing excess adhesive to the peripheral end of the concave lens 1, and an adhesive discharge hole as necessary. 14 may be provided. The combination of lenses is not limited to this embodiment, and may be a combination of three or more lenses.

As an adhesive for forming the adhesive layer 3, one which does not contain a solvent and has a small curing shrinkage is preferably used. Here, if the adhesive forming the adhesive layer 3 is a so-called solvent type, when the lens to be bonded is made of plastic, the lens may be attacked by the solvent,
Since the solvent volatilizes and the volume of the adhesive layer 3 is reduced, the intended optical characteristics of the laminated color lens may be impaired.

Preferred adhesives include, for example, epoxy resin adhesives and addition type silicone adhesives. In particular, the addition type silicone adhesive has a curing shrinkage of 1% or less, preferably about 0.2%, which is significantly higher than the curing shrinkage of the epoxy resin adhesive of about 5 to 8%. Since the shrinkage rate is small, the desired optical characteristics are not impaired. Further, since it has flexibility even after being cured, even if a deformation such as a heat deformation or a moisture absorption deformation occurs in one lens, there is an advantage that the influence of the deformation does not easily reach the other lens.

The addition type silicone adhesive has a curing mode of any one of a heat curing type, a room temperature curing type and a UV curing type, and more specific examples thereof include an addition type silicone rubber and an addition type silicone gel. Be done. The refractive index is usually about 1.40 to 1.53, preferably about 1.49 to 1.53. Such an addition type silicone adhesive is used, for example, in a silicone potting material for electronics [TSE 30
62 ”], UV curable liquid silicone [manufactured by Toshiba Silicone Co., Ltd.,“ TFC 7770 ”,“ TFC 7870 ”] and the like.

The light-absorbing substance contained in the adhesive layer 3 is appropriately selected from various dyes and pigments having a desired light-absorbing property. Specifically, for example, in the case of a laminated color lens that constitutes a projection device used for a G (green) projection tube in a projection television, phthalocyanines, especially 600 nm
Copper phthalocyanines that absorb light of wavelengths in the vicinity and have excellent light resistance are preferably used. For example, such copper phthalocyanines are represented by the following formula (1).

[0019]

[Equation 1] Further, in the case of a laminated color lens that constitutes a projection device used for an R (red) projection tube in a projection television, for example, an anthraquinone dye represented by the following formula (2) is preferably used.

[0020]

[Equation 2] The addition ratio of the light absorbing substance in the adhesive layer 3 varies depending on the kind of the light absorbing substance, and therefore it is difficult to determine uniformly. For example, the addition type silicone adhesive may be added with the copper phthalocyanine. When added, usually
It is about 0.01 to 5.00% by weight.

In order to color the adhesive layer 3 with the light absorbing substance, the adhesive forming the adhesive layer 3 and the light absorbing substance may be kneaded. The thickness of the adhesive layer 3 is usually several μm to 1 m.
It is about m, preferably about 0.1 to 1 mm.

A laminated color lens 30 having this structure
Is, for example, as shown in FIG.
1, 52, 53, 54, 55, 56, projection tube (CRT)
60 and the frame 70 are particularly preferably used for constructing a projection television projection apparatus, and the projection television using the laminated color lens 30 of this construction has improved color purity.

[0023]

EFFECTS OF THE INVENTION According to the present invention, because of the above-mentioned constitution, even if it has a uniform filter characteristic and the change of the filter characteristic is small, and a laminated color lens of another color is manufactured. There is no need to prepare lenses of different colors, and therefore, there is no need to wash a mold and a molding machine at the time of lens molding, and a bonded color lens having an advantage that it can be efficiently manufactured in a simplified process is provided. Provided.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an example of a laminated color lens of the present invention.

FIG. 2 is a plan sectional view showing another example of the laminated color lens of the present invention.

FIG. 3 is a cross-sectional explanatory view showing a configuration example of a projection device of a production television using the laminated color lens of the present invention.

FIG. 4 is a plan sectional view showing an example of a conventional bonded color lens.

[Explanation of symbols]

 1 ... concave lens 2 ... convex lens 3 ... adhesive layer

Claims (1)

Claim: What is claimed is: 1. A bonded color lens comprising a plurality of lenses bonded together via an adhesive layer, wherein the adhesive layer is colored with a light absorbing substance that absorbs light of a specific wavelength. A laminated color lens characterized in that