NIGHT VIEWING POCKET SCOPE

• US 3,803,407 A
• Filed: 08/18/1972
• Issued: 04/09/1974
• Est. Priority Date: 08/18/1972
• Status: Expired due to Term

• Current Assignee: David Kent Anderson
• Original Assignee: David Kent Anderson
• Inventors: Anderson, David K.
• Primary Examiner(s): Borchelt, Archie R.
• Assistant Examiner(s): Grigsby, T. N.
• Application Number:
  US05/281,681
• Time in Patent Office: 599 Days
• Field of Search: 250/213VT,227,239
• US Class Current: 250/214.0VT
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification

Abstract

An electro-optic pocket scope that provides a highly intensified image of low light level scenes being viewed therethrough. The pocket scope is similar to a simple telescope in that an optical train of elements comprise an objective lens for obtaining the image and a magnifier eye piece to display the scene to the observer'"'"''"'"'s eye. The present scope is different in that photons from the objective lens are focused on a photocathode through collecting fiber optics, are converted into an electron image that is intensified through a microchannel plate, is reproduced as a visual image on a green phosphor screen, is inverted through a fiber optic inverter an is then presented to the magnifier eye piece for observation by an operator. Salient features of this invention are the high amplification of the electron image by the microchannel plate, the high resolution of the visible image through the collecting fiber optics and the fiber optic inverter, and the use of the more efficient green phosphor for the screen. These features increase brightness from the scene being viewed to the observer by a factor of many thousands. The microchannel plate electron multiplier, or amplifier, is the primary gain element of the pocket scope. The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

Claims

1. A night viewing pocket scope having an optical train of elements comprising:

an objective lens for obtaining an image of a nighttime scene and providing a focused image therefrom;

collecting fiber optics positioned in the focal path adjacent said objective lens;

a cathode layer deposited on the side of said collecting fiber optics that is opposite said objective lens, said cathode ejecting electrons therefrom according to said focused image;

a microchannel plate electron multiplier tube having an input electrode adjacent said cathode layer and an output electrode on the opposite side of said microchannel plate electron multiplier tube, said tube used for multiplying the electron ejected from said cathode;

a fiber optic inverter positioned adjacent said output electrode;

a phosphor screen layer deposited on the side of said fiber optic inverter adjacent said output electrode for receiving electrons emitted from said tube and providing a luminescent image therefrom wherein said fiber optic inverter turns said luminescent image through 180*;

a direct current power supply for furnishing operating voltages to said cathode, tube, and phosphor screen; and

a magnifier eye piece for viewing said luminescent image.

2. A night viewing pocket scope as set forth in claim 1 wherein said night viewing pocket scope is 18 millimeters in diameter.

3. A night viewing pocket scope as set forth in claim 1 wherein said magnifier eye piece has a magnification power in the range from 10 to 14.

4. A night viewing pocket scope as set forth in claim 1 wherein said phosphor screen is made of green material.

5. A night viewing pocket scope as set forth in claim 1 wherein said cathode is made of a mixture of sodium, potassium, cesium, and antimony.

6. A night viewing pocket scope as set forth in claim 1 wherein said phosphor screen is made of a mixture of zinc, cadmium sulphide, and silver.