Patent ID: 9176398
Filing Date: 2015-11-03
Classification: G02B,G03F,G21K

Abstract:
1. A method for thermally conditioning an optical element supported by a support, the method comprising: irradiating the optical element with radiation; not-irradiating the optical element with the radiation; allowing heat flow between the optical element and a conditioning fluid that is held in a conditioning fluid reservoir in the support; and providing a fluid flow of the conditioning fluid, to supply thermally conditioned fluid to the reservoir, wherein a flow rate of the fluid during the irradiating of the optical element is lower than a flow rate of the fluid when the optical element is not-irradiated, wherein the fluid flow rate is substantially zero during the irradiating, and wherein pressure variations of the conditioning fluid are counteracted in order to keep a fluid pressure of the conditioning fluid in the reservoir at or near a predetermined fluid pressure range.