Optical system element, for receiving a pressurised functional fluid

An element of an optical system including:

• a first enclosure for receiving in circulation a functional fluid;
• and
• an inlet window and an outlet window located on the first enclosure, the inlet window configured to allow a light beam to pass into the first enclosure and the outlet window configured to allow a light beam to pass out of the enclosure;
• wherein:
• each of the inlet window and the outlet window includes two viewports which laterally delimit a spacer cavity adjacent to the first enclosure,
• the spacer cavity is configured to receive a second fluid, having a predetermined optical index, and is provided with a pressure adjusting device therewithin,
• the second fluid has an optical index substantially equal to that of one of the functional fluid and an ambient medium surrounding the element, within plus or minus 10%, and
• the pressure adjusting device is adapted for the pressure within the spacer cavity to be substantially equal to a pressure of the other of the functional fluid in the first enclosure and the ambient medium, within plus or minus 10%.

An element of an optical system including:

• a first enclosure for receiving in circulation a functional fluid;
• an inlet window and an outlet window located on the first enclosure,
• wherein:
• each of the inlet window and the outlet window includes two viewports which laterally delimit a spacer cavity adjacent to the first enclosure,
• the spacer cavity is configured to receive a second fluid, having a predetermined optical index, and is provided with a pressure adjusting device therewithin,
• the second fluid has an optical index substantially equal to that of one of the functional fluid and an ambient medium surrounding the element, within plus or minus 10%, and
• the pressure adjusting device is adapted for the pressure within the spacer cavity to be substantially equal to a pressure of the other of the functional fluid in the first enclosure and the ambient medium, within plus or minus 10%, and
• a light injection port arranged in the spacer cavity separate from each of the inlet window and outlet window, wherein the inlet window and the outlet window are configured to allow a light beam injected into the spacer cavity through the light injection port to pass out of the enclosure.