JPS606901A - Variable focus lens - Google Patents

Abstract

PURPOSE:To obtain a large-diameter convex/concave lens at low cost by fixing two transparent flat plates at their outer circumferential parts while leaving a specific interval, and feeding or discharging transparent liquid to and from between them and varying the surface curvature of the plates. CONSTITUTION:The two transparent flat plates 1 and 2 which have flexibility are fixed to a holding member 3 in a liquid-tight state at their circumferential edges. When a variable focus lens is formed, transparent liquid 7 from a tank 8 is charged by a pump 6 into the space 4 through a liquid intake and outlet 3a through a pipe 5 and air bubbles in the space 4 are removed completely. When the pressure in the liquid in the space 4 is further raised by the pump 6, the plates 1 and 2 are curved gradually as shown by broken lines 1' and 2' to form a large-diameter lens of curved plates 1' and 2'. The space is reduced in pressure by the pump 6 to obtain a concave lens similarly.

Description

[Detailed description of the invention] This invention relates to variable focus lenses.

Conventionally, variable focus lenses that combine multiple lenses and relatively displace them have been used, but optical lenses that can change the focus of the lenses themselves have not been used. Optical lenses currently in use are fixed-focus lenses made of transparent materials such as glass and plastic, whose surfaces are shaped into a predetermined curvature. However, if we try to use this for astronomical telescopes or solar heat harvesting devices that require particularly large apertures, a large amount of money will be required for the fabrication of the material and the work required to achieve a certain curvature. becomes. In particular, it has not been economical for spherical lenses used in ICs and pyrolysis to raise the temperature of heat media in household solar heat harvesting systems.

The object of the present invention is to overcome the above-mentioned conventional drawbacks, and to fix two transparent flat plates at the outer periphery at a constant interval, and to feed or discharge a transparent liquid between the two transparent flat plates. By changing the curvature of the surfaces of the two transparent flat plates, a relatively thick convex, concave, or cylindrical lens with a diameter of I can be realized at low cost, and the object to be heated or the necessary point or line can be formed at a low cost. The object of the present invention is to provide a variable focus lens that can form an image simply by changing the pressure of a liquid.

Next, the present invention will be described by way of examples with reference to the drawings.

FIG. 1 is a cross-sectional view of one embodiment of the present invention, in which two flexible transparent flat plates 1 and 2 are fixed to a holding member 6 at their peripheral edges in a liquid-tight manner. In this state, the interval between the two flat plates 1 and 2 is constant, and a space 4 is formed. As the two flat plates 1.2, for example, a circular plate is used when realizing a spherical lens, and a rectangular plate is used when realizing a cylindrical lens. The holding member 3 is provided with a liquid inlet/outlet hole 3a,
A pipe 5 communicates with this. A pump 6 for feeding a transparent liquid into the space 4 is disposed in the middle of the pipe 5, and the end of the pipe 5 is connected to a tank 8 that stores a transparent liquid 7.

To form a variable focus lens, the transparent liquid 7 is caused to flow from the tank 8 through the tube 5 into the space 4 through the liquid inlet/outlet hole 3a using the pump B, and at the same time, air bubbles in the space 4 are completely removed. Removal of air bubbles can be easily achieved, for example, by providing an exhaust hole (not shown) in the holding member B and closing the exhaust hole when the space 4 is filled with the liquid 7 and the air bubbles are completely removed. As the pressure of the liquid in the space 4 is further increased using the pump 6, the flat plates 1 and 2 gradually curve into shapes as shown by broken lines 1' and 2'. At this time, since the flat plates 1 and 2 and the holding part 3 are liquid-tightly joined as described above, even if there is a difference between the pressure inside the space 4 and the external pressure, the liquid will not leak. , or no air can enter from outside. If the flat plates 1 and 2 are disks, it is possible to create a curved surface approximately similar to a spherical h 11,
When the flat plates 1 and 2 are rectangular, a curved surface close to a cylindrical surface can be obtained except near the ends of the short sides. Since the flat plates 1, 2 have a uniform thickness, their presence can be almost ignored optically, and the liquid in the space 4 acts as a lune.

FIG. 2 shows a concave lens according to the present invention, in which the space 4 is once filled with a transparent liquid, and then a part of the liquid is drained out by a pump B, thereby forming a flat plate 1.2, indicated by a broken line.
A concave lens is formed by deforming it like ", 2".

In Figure 3, a soft object is used as the flat plate 1 and a hard substance is used as the flat plate 2.
A convex plano lens formed by increasing the pressure in the space 4 and deforming the flat plate 1 to 1'' is shown.

In this way, various types of lenses can be realized by various combinations.

Further, by changing the pressure of the liquid in the space 4, lenses with various curvatures can be realized, and the curvature can also be changed continuously.

As the liquid 7 filled in the space 4, water, transparent resins such as silicone resin, transparent alcohols, ethers, etc. can be used. On the other hand, for the transparent flat plates 1 and 2, synthetic resins such as styrene resin, acrylic resin, and polycarbonate resin, quartz glass, lead glass, and other glasses are used, and of course an anti-reflection coating is applied to the surface. You can also do that.

The thickness of the space 4 between the flat plates 1 and 2, that is, the flat plates 1 and 2
The distance between the two may be increased or decreased as necessary, or it may be approximately zero.

As explained above, according to the present invention, the transparent flat plates 1 and 2 need only be flat, so large-area, high-quality plates (for example, polished plate glass) can be obtained at relatively low cost, and therefore, large-diameter lenses can be used. can be realized at low cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view of one embodiment of the invention, FIG. 2 is a sectional view of another embodiment of the invention, and FIG. 3 is a sectional view of another embodiment of the invention. 1.2... Transparent flat plate 6... Holding member 4... Space 5... Tube 6... Pump 7... Transparent liquid 8・・・・・・Tank patent applicant Mitsui Toatsu Kikou Co., Ltd.

Claims (1)

[Claims] two transparent flat plates, at least one of which is flexible and arranged parallel to each other and facing each other; a holder that holds the two flat plates liquid-tight at their peripheral edges; A transparent liquid is contained between two flat plates, and the curvature of at least one of the two flat plates is changed by adjusting the pressure and/or amount of the liquid. variable focus lens.