Research/Patents/US 5301009
US 5301009

FRUSTRATED TOTAL INTERNAL REFLECTION OPTICAL POWER LIMITER

Assignee

UNITED STATES OF AMERICA AS REPRESENTED BY THE SECRETARY OF THE ARMY, THE

Filed

Apr 28, 1983

Granted

Apr 5, 1994

Location

OAKTON VA US

Abstract

In order to protect a delicate photo-detector from high-intensity optical radiation such as from a laser, a device for limiting power to the detector is interposed between the radiation and detector. This device has two embodiments and is made such that high-intensity radiation is totally reflected. In the absence of high-intensity radiation, total reflection is frustrated, and desired radiation passes to the detector. Both embodiments use two prisms with parallel surfaces skewed to incident radiation and with a slightly absorbant optical material between the surfaces. Desired radiation normally passes through the prisms and the material to the detector. In one embodiment, the material is a liquid which vaporizes in response to high-intensity radiation, and in the other embodiment, the material expands and pushes the prisms apart. In either case, transmission of radiation halts, and the radiation is totally reflected by a prism skewed surface.

Source: Google Patents

35 USC §181 Secrecy Order

Imposed

Nov 27, 1985

Rescinded

Oct 4, 1993

Duration

7 years, 10 months

Inventor

  • 1RICHRD R. SHURTZ

Technology Domains

Click a domain to browse all patents in this category.

Back to patent indexSource: USPTO 35 USC §181 secrecy order records