Patent ID: 7044611

Claim:
An optical device for use under significantly varying ambient pressure comprising: a housing, a transparent element, a first sealing device and a protection apparatus; said housing having an interior part, an environment outside said housing and a recess in a first region; said transparent element being arranged in said first region in a region of said recess; said first sealing device sealing a first sealing gap between said transparent element and said housing; said first sealing device sealing said interior part of said housing relative to said environment of said housing up to a first pressure level; said protection apparatus being arranged outside said housing and being displaceable from a first functional position into a second functional position; said protection apparatus, in said first functional position, covering said transparent element and sealing said first region relative to said environment of said housing in such a way that a pressure in an intermediate space between said protection apparatus and said first region is not higher than said first pressure level if an ambient pressure in said environment of said housing exceeds said first pressure level; said protection apparatus, in said second functional position, leaving said transparent element uncovered.