MANUFACTURING A HIGH PERFORMANCE

POLARIZING PRISM

BACKGROUND OF THE INVENTION 1. Field of the invention

The present invention relates to fee method of forming an air gap for manufacturing a high performance polarizing prism for a polarization watch.

2. Description of the background

The beneficial effects that the polarized light gives the living things are being verified practically. Therefore, it is true that the need for the polarizing prism with high transmittancy and high polarizing purity that is more effective for human body is increasing actually. The degree of polarization was approximately 10 ^"2 where laser beams were incident perpendicularly upon the front of the polyvinyl alcohol filrn polarizer in Korean Patent No.42430 "Technique for manufacturing a blood purifier for health" Korean Patent No.43854 "Process for manufacturing the natural high purity iceland spar crystal" described the processing and structure of the polarizing prism, which can be used in the minimal mechanical structure, such as a single polarizing prism, mosaic polarizing prism, optical glass & iceland spar polarizing prism and a single prism without nonpolarized light Where laser beams {wavelength: 532 nrn, diameter of beams: approx. 1 mm) were incident perpendicularly upon the single iceland spar polarizing prism the degree of polarization 2mm far from the top of the prism was nearly 10 ^"3 - 10- ⁴ . At present the high performance polarizing prisms are more increasingly needed in public health as well as the laser technology because it is effective for prevention and cure of diseases including the increase of the amount of the circulating blood flow in human body, typically in the brain and heart, and recovering various metabolic disorders.

But no method for manufacturing the polarizing prism that has high transmittancy, high extinction ratio, shorter aperture than length and wide wave band, especially method for improving performance of the polarizing prism has been described. The shapes and structures of Glan Thomson polarizing prism, Glan Laser polarizing prism, Wollaston polarizing prism and so on were described in the publications such as "θπTHKO-3JIEKTPOHHtIE IIOJLaPH3 AHHOHHBIE yCTPOHCTBA (Electro-optical Polarizing Equipments)" and "πθJiaPH3AπHOHHLIE πPH3MH OB3OP (Summary of Polarizing Prisms)" from the former Soviet Union, and " M Jt t ^ m 3fe Ψ (Polarization and Crystal Optics)" and "Mmi'M&MJtΨMmi (Various High Quality Optical Components)", etc., but no processing method, especially some technical features for improving polarizing purity such as the size of an air gap and the method of forming the air gap were. In addition the polarizing prisms of which the interface between two right- triangle prisms is connected by an optical adhesive have a big Length/Aperture ratio, 2.5-3.0, and so they can't be used in the limited structures such as a ring or a watch.

SUMMARY OF THE INVENTION

The objective of the present invention is to establish the method of forming an air gap for manufacturing a high performance polarizing prism for a polarization watch which has high transmittancy, high extinction ratio and small Length/Aperture ratio.

In order to manufacture such a high performance polarizing prism it is required that a regular air gap should be formed between two right-triangle prisms which are obtained from one iceland spar crystal cube, of which the optical axis is set, and so have the same optical characteristics. This problem can be solved by applying the screen printing.

Prior to the screen printing two right-triangle prisms which have the same optical characteristics and the suitable size and Length/Aperture ratio for providing a polarization watch with them, and a 180 to 280-mesh screen with 0.06 to 0.15 mm of thickness which is fixed in a rectangle-shaped frame should be prepared. For providing a polarization watch with a prism its Length/Aperture ratio should be 0.5 to 1.

The method of forming an air gap using the screen printing comprises the following steps:

First, coating the screen with the sensitizer in a darkroom, Second, taking a picture of the original painting for the screen printing and making the positive film,

In the original painting zonal black lines with 0.2-0.4 mm of width are only drawn respectively on a pair of edges of the rectangle which is the same size as the air interface of the right-triangle prism. Third, printing down the screen coated with the sensitizer and then developing it, - A -

The screen is printed down for a certain time after adhered closely to the positive film on the glass plate of the printing-down apparatus, and then is developed in the water at ordinary temperature.

Fourth, printing the image of the screen on the air interface of a right- triangle prism, and

By according the image of the screen with the air interface of the prism and then printing it the zonal printed layers with the same width as the screen are formed on each of two edges of the air interface.

Fifth, assembling the printed right-triangle prism with the imprinted one which has the same optical characteristics as the printed one.

The prisms are fixed by according the air interface of the printed prism with the air interface of the unprinted one which has the same optical characteristics as the printed one and putting them in an acrylic resin case for a polarizing prism in a watch.

The high performance polarizing prism manufactured like this shows various beneficial effects for human body by being installed in the limited structures such as a polarization watch.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 shows a right-triangle prism used in manufacturing a high performance prism according to an embodiment of the present invention. Fig. 2 shows a positive film of the original painting used in the screen printing according to an embodiment of the present invention. Fig. 3 shows the screen printed down and developed according to an embodiment of the present invention. Fig. 4 shows the air interface of the printed right-triangle prism according to an embodiment of the present invention.

Fig. 5 shows the high performance polarizing prism fixed in an acrylic resin case according to an embodiment of the present invention. Fig. 6 shows a polarization watch where a high performance polarizing prism is installed according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Fig. 1 shows a right-triangle prism used in manufacturing a high performance prism according to an embodiment of the present invention. In Fig. 1 the air interface 11 of the right-triangle prism 10 is a rectangle and is screen-printed. "L" and "A" is the length and aperture of the right-triangle prism 10, and the angle α is 90 degrees. In one embodiment of the present invention prior to the screen printing a iceland spar crystal with high optical quality that has no straie, cracks, diffusion and impurities is, after adjusting its optical axis, cut with a cutting angle, 49°63', and separately processed. Then two right-triangle prisms which have the same optical characteristics are taken.

Fig. 2 shows a positive film of the original painting used in the screen printing according to an embodiment of the present invention. In Fig.2 only two zonal black lines 21 are on a positive film. The dotted portion indicates the same rectangle as the air interface 11 of the right-triangle prism. The zonal black lines 21 are accorded with each one of two edges of the air interface 11 of the right-triangle prism 10. - Q -

Fig. 3 shows the screen printed down- and developed according to an embodiment of the present invention. In Fig. 3 as a screen 30 coated with the sensitizer is printed down the illuminated portion 31 is hardened. And then only the image 32 remains on it as the screen 30 is developed. In one embodiment by adhering the screen 30 coated with a sensitizer closely to the positive film 20 and then illuminating it for about 20 minutes the other portion 31 of the screen 30 except for the portion under the zonal black line 21 is hardened. Then the screen 30 printed down is developed in the water at ordinary temperature and as the result the sensitizer on the portion under the zonal black line 21 is removed, and the image 32 is made which has the same size as the zonal black line 21.

Fig. 4 shows the air interface of the printed right-triangle prism according to an embodiment of the present invention. In Fig. 4 as the image 32 of the screen 30 is printed on the air interface 11 of the right-triangle prism 10 the printed layer 41 is made. The thickness of the printed layer 41 is the same as the screen 30 and its width is the same as the zonal black line 21. In one embodiment the thickness of the screen 30 is 0.09 mm and so the width of the printed layer 41 is also 0.09 mm.

Fig. 5 shows the high performance polarizing prism fixed in an acrylic resin case according to an embodiment of the present invention. In Fig. 5 the imprinted right-triangle prism 52 is on the printed right-triangle prism 51 and both of them are fixed in an acrylic resin case 53. In one embodiment as the printed right-triangle prism 51 is first put in the acrylic resin case 53 and then the imprinted right-triangle prism 52 is fixed on it the air gap between those two prisms is maintained constant. This air gap is as thick as the printed layer 41 and after all its thickness is the same as the screen. And the wavelength range of the high performance polarizing prism is 215 to 2300 run and the prism has a high extinction ratio, 1 X 10 ^"6 .

Fig. € shows a polarization watch where a high performance polarizing prism is installed according to an embodiment of the present invention. In Fig. 6 a high performance polarizing prism 61 is installed on the right of the polarization watch 61.

In one embodiment the polarization watch 60 is an analogue crystal clock and the high performance polarizing prism 61 is cube-shaped 10 mm long, 7 mm wide and 6 mm high.