OPTICAL FLUID LENS CONSTRUCTION

• US 3,738,734 A
• Filed: 02/23/1972
• Issued: 06/12/1973
• Est. Priority Date: 02/23/1972
• Status: Expired due to Term

• Current Assignee: Stuart S. Tait, Thomas T. Reider
• Original Assignee: Stuart S. Tait, Thomas T. Reider
• Inventors: Tait, Stuart S., Reider, Thomas T.
• Primary Examiner(s): Corbin, John K.
• Application Number:
  US05/228,634
• Time in Patent Office: 475 Days
• Field of Search: 350/179,180
• US Class Current: 359/665
• CPC Class Codes: G02B 3/12 Fluid-filled or evacuated lenses
• CPC Class Codes: G02B 30/56 by projecting aerial or floating images

Abstract

This invention provides a liquid-filled lens, which incorporates means for causing atmospheric pressure at least partly to counteract the internal pressure arising from the static pressure of the liquid head. This is accomplished generally by lowering the atmospheric equivalent level below the top of the chamber. Preferably, the latter is specifically carried out by making the chamber within the liquid lens air-tight except for an opening connected to an open-ended tube, the other end of the tube being immersed below the level of a liquid in a receptacle, the level of the liquid in the receptacle being below the top of the chamber, and preferably in the area between the bottom of the chamber and a point about one-third of the way between the bottom and the top of the chamber.

Claims

1. An optical device comprising two juxtaposed transparent walls defining between them a chamber holding a transparent liquid, each wall having optically smooth inner and outer surfaces, the inner surfaces of the walls being configured to each other as the surfaces of a lens, and means for decreasing the absolute pressure at the top of the chamber below atmospheric, whereby the atmospheric equivalent level is lowered a significant distance below the top of the chamber, said means including aperture means located below the top of said chamber for communicating the liquid of said chamber with a location within a receptacle, said location being submerged within the liquid in said receptacle, the chamber being sealed apart from said aperture means.

2. An optical device as claimed in claim 1, in which each transparent wall is colorless and has a substantially uniform thickness.

3. An optical device as claimed in claim 2, in which the said lens is a magnifying lens, the transparent walls being of clear plastic.

4. An optical device as claimed in claim 3, further including a piece of rear-projection material arranged on the optical axis of the device and spaced therefrom by a distance less than the focal length thereof.

5. An optical device as claimed in claim 2, in which the said lens is double-convex, each wall having a substantially spherical curvature.

6. An optical device as claimed in claim 1, in which the said means for decreasing functions as a result of the pull of gravity.

7. An optical device as claimed in claim 1, in which said receptacle is open to the atmosphere, the receptacle being adapted to be positioned such that, when the mid-plane between the walls is substantially vertical, the said location is submerged beneath an air-liquid interface in said receptacle, which interface is located on a level below the upper most part of the chamber.

8. An optical device as claimed in claim 1, in which the aperture means includes a tube communicating the chamber with said location, said receptacle being positioned such that the said location is submerged beneath and air-liquid interface in said receptacle, which interface is located on a level closEr to the lowermost part of said chamber than to the uppermost part of said chamber, each wall being colorless and having a substantially uniform thickness, the said lens being a magnifying lens.

9. An optical device as claimed in claim 1, which device further includes reservoir means adapted to receive any overflow from said receptacle and any leaks from said chamber, the reservoir means having a capacity greater than the volume of said chamber, the device further including magnification indicating means for indicating the distance of an object from the lens at which a given degree of magnification of that object will take place.

10. An optical device comprising two juxtaposed transparent walls defining between them a chamber holding a transparent liquid, each wall having optically smooth inner and outer surfaces, the inner surfaces of the walls being configured to each other as the surfaces of a lens, and means for decreasing the absolute pressure at the top of the chamber below atmospheric, whereby the atmospheric equivalent level is lowered a significant distance below the top of the chamber, said means including aperture means located below the top of said chamber for communicating the liquid of said chamber with a location within a receptacle, said location being submerged within the liquid in said receptacle, the chamber being sealed apart from said aperture means, a drill-hole in one wall below the top of the chamber, the outer end of the drill-hole lying wholly above the inner end thereof when the optical device is oriented with the walls substantially vertical, the atmospheric equivalent level being located vertically between the outer and inner ends of said drill-hole.

11. An optical device as claimed in claim 10, in which the drill-hole is located about one-third of the way from the bottom to the top of the chamber.