De-icing or defogging system for optical instrument and image acquisition device provided with said system
View Patent ↗The disclosed embodiments relate to a defogging or de-icing system for an optical instrument including a protection housing. According to the disclosed embodiments, the system includes: a porthole covered on at least one face thereof with a heat conducting film provided at the edge of the useful area of said porthole, the porthole being mounted on the protection housing, heating members placed in contact with the film for heating said film, and a power supply circuit for the heating members.
1. A defogging or de-icing system for an optical instrument having a protective casing, wherein the defogging or de-icing system comprising:
a porthole mounted on the protective casing;
a plurality of heating elements;
a compressible, annular heat conducting film placed at an edge of the porthole and conforming to a shape of the heating elements when compressed between the edge of the porthole and the plurality of heating elements; and
an electrical supply circuit for said heating elements.
2. The system as claimed in claim 1 , wherein said conducting film comprises a substrate having glass fibers and on its outer faces layers comprising silicone polymers filled with heat conducting particles.
3. The system as claimed in claim 1 , wherein said electrical supply circuit includes a printed circuit on which the heating elements are mounted, said printed circuit being designed to supply said heating elements with power.
4. The system as claimed in claim 3 , wherein said printed circuit has an annular form.
5. The system as claimed in claim 1 , wherein said heating elements are resistances designed to at least partially cover said heat conducting film.
6. The system as claimed in claim 1 , further comprising another heating element designed to be placed in said casing.
7. An image acquisition device having a protective casing in which at least one sensor is placed, said casing having a porthole placed in front of the sensor, the image acquisition device further comprising a defogging or de-icing system as claimed in claim 1 .
8. The device as claimed in claim 7 , wherein said casing is a watertight casing filled with nitrogen.
9. An aircraft equipped with an image acquisition device as claimed in claim 7 .