JPS59137903A - Optical element and its production - Google Patents

Abstract

PURPOSE:To obtain an optical element which is easy to handle and is convenient in mounting by providing a plate-shaped flange thinner than wall thickness of an optical member in the peripheral edge of the optical member. CONSTITUTION:Solder for non-metals consisting of Sa, Pb, Mn, etc. is coated on the peripheral edge 11 of a mirror base plate 1, and said solder is also coated on the inside periphery of a discoid flange 3 and near the same 31. The solder coating is accomplished by using the solder for non-metals in the same way as mentioned above if an insulating material is used for the flange 3. The flange 3 having the thinner wall thickness than the base plate 1 is used. The flange 3 is then inserted into the peripheral edge of the plate 1 and while the assembly is heated by a heater 5, the joint part between the plate 1 and the flange 3 is soldered. The surface of the plate 1 fixed with the flange 3 is polished by a polishing device 6 and is further subjected to a desired coating treatment by a vacuum deposition device 7. A reflection mirror provided with the flange 3 at the peripheral edge of the plate 1 is thus produced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical element and a method for manufacturing the same, and more particularly to an optical element such as a lens, window, or reflective mirror having a novel configuration and a method for manufacturing the same.

As is well known, in a laser resonator, a pair of reflecting mirrors are arranged parallel to each other at both ends of a discharge tube. Generally, these reflective mirrors are made of Si. A disk-shaped semiconductor substrate made of Ge or the like is used, and the reflective surface is subjected to a desired optical coating process. These reflecting mirrors are firmly fixed to mirror holders provided at both ends of the discharge tube.

By the way, when such a mirror is used in a sealed-off type laser, it is necessary to fix it hermetically to a mirror holder in order to maintain a constant low vacuum state inside the discharge tube. However, mirrors used for infrared wavelength lasers have a problem in that the coding layer on the reflective surface is sensitive to heat and can only withstand temperatures of about 200°C. Therefore, the fixation of the mirror and the mirror holder had to be by fusion using In solder. In solder is expensive and has a melting point of 157°C.
Therefore, the manufacturing cost of the laser resonator increases, and manufacturing is not easy due to thermal considerations for the mirror.

On the other hand, when such a mirror is used in a gas flow type laser, it is pressed and fixed to a mirror holder by mirror rolling and a rolling press. However, in conventional mirrors, the pressure imparts mechanical distortion to the mirror, which is undesirable as it may disrupt the optical alignment. Particularly, in the case of a high-output laser, the distortion caused by (■) is added to this mechanical distortion, and there is even a risk of mirror destruction.

Furthermore, when these conventional mirrors are touched directly with the hands, the reflective surface often becomes dirty, and the mirrors must be handled with bamboo scissors or other appropriate means. Therefore, care was required during the packaging work and the work of assembling it into the device, which was troublesome.

The present invention aims to eliminate the above-mentioned drawbacks, and relates to an optical element such as a reflective mirror in which a disc-shaped flange is provided on the peripheral edge of the optical element, and a method for manufacturing the same.

The present invention will be explained in detail below. FIG. 1 is a cross-sectional schematic diagram of certain embodiments of the present invention. 1 in the figure is the substrate of the reflective mirror,
2 is the metal fusion part as described later, 3 is the flange, and 4 is the metal fusion part.
shows a coating layer applied on mirror substrate 1. FIG.

The mirror substrate 1 is made of a semiconductor material such as Si or Ge.

The flange 3 is formed into a disk shape and is made of metal or an insulating material. The flange 3 is formed to have a thinner wall thickness than the mirror substrate 1, and is fixed to the peripheral edge of the mirror substrate 1.

When an insulating material is used for the flange 3, for example, ceramic is used.

The mirror substrate 1 and the flange 3 are firmly fixed by a metal fusion part 2. The fused portion 2 is made of solder.

Next, an embodiment of the manufacturing method of the present invention will be described based on FIG.

First, a solder coating is applied to the peripheral edge 11 of the mirror substrate 1 using a non-metallic solder.

The solder is a solder made of Su, Pb, Mn, etc.
For example, one commercially available under the trade name "Cerasolza" is used. Incidentally, this work is done by ultrasonic soldering.

In addition, the inner circumferential portion and the vicinity of the inner circumferential portion 31 of the disc-shaped flange 3
Also solder coating is applied.

When an insulating material is used for the flange 3, the coating is performed using non-metallic solder as described above.

As described above, the flange 3 is thinner than the mirror substrate 1.

Next, the flange 3 is inserted into the peripheral edge of the mirror substrate 1, and while the mirror substrate 1 and flange 3 are heated by the heater 5, the joint between the mirror substrate 1 and the flange 3 is soldered.

At this time, solder coating has already been applied to the outer periphery of the mirror substrate 1, the inner periphery of the flange 3, and the vicinity thereof. Therefore, soldering can be easily performed at the joint between the mirror substrate 1 and the flange 3, and both can be firmly fixed.

The surface of the mirror substrate 1 to which the flange 3 is fixed is polished. Needless to say, the mirror substrate 1 is polished by a known polishing device 6.

At this time, since the flange 3 is thicker than the mirror substrate 1, the mirror substrate can be polished with the flange 3 fixed.

The polished mirror substrate 1 is then subjected to a desired coating treatment. The coating process is performed by, for example, a vacuum evaporation device 7.

In this way, a reflective mirror in which the flange 3 is provided on the periphery of the mirror substrate 1 is manufactured. Incidentally, either the process of applying plating to the peripheral edge of the mirror substrate 1 or the process of applying plating to the inner peripheral part of the flange 3 and its vicinity may be performed first.

The reflective mirror shown in the above embodiment is provided with a flange at the peripheral edge of the mirror, and the flange is fixed when the mirror is fixed to the mirror holder.

Therefore, when using this mirror in a sealed laser,
Metal fusion or glass fusion can be performed without thermally damaging the coating layer. Therefore, the device can be manufactured easily at low cost. Furthermore, even when used in a gas flow type laser, no mechanical strain is applied to the mirror substrate, which is convenient. In addition, when handling the mirror, you only have to grasp the flange, so you don't have to worry about handling it.Furthermore, if the flange is made of a material with good thermal conductivity, such as copper, it is convenient for cooling the mirror. Further, if an insulating material is used for the flange, it is convenient to insulate the mirror and the mirror holder.

These effects are achieved not only when the flange is provided on a window or a lens, but also on a reflective mirror.

According to the present invention, an optical element is constructed that is easy to handle and convenient for installation. In addition, manufacturing of the optical element is also easy.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing a certain embodiment of the present invention. FIG. 2 is an explanatory diagram showing an embodiment of the manufacturing method of the present invention. Reference numerals in the drawings include: 1...Mirror substrate, 2...Solder fusion part, 3...Flange, 11...Mirror substrate periphery, 31...Inner periphery of the flange and the vicinity of the inner periphery.

Claims (1)

[Scope of Claims] 1) An optical element characterized in that an optical member having a predetermined function is provided with a plate-shaped flange that is thinner than the wall thickness of the optical member at the peripheral edge thereof. 2) Apply solder coating to the peripheral edge of the optical member,
and a step of applying solder coating to the inner periphery of a hollow plate-shaped flange thinner than the wall thickness of the optical member and a position near the same, and inserting the flange to the peripheral edge of the optical member and heating both. An optical system comprising the steps of soldering the joint, polishing the surface of the optical member to which the flange is fixed, and applying optical coating to the surface of the optical member to which the flange is fixed. Method of manufacturing elements.