Abstract: The invention relates to fluorine-containing silica glasses, and methods of their production. The silica glass may be used for an ultraviolet light optical system in which light in a wavelength region of 200 nm or less, such as an ArF (193 nm) excimer laser, is used. The invention also relates to a projection exposure apparatus containing fluorine-containing glass of the invention.

Abstract: A high-voltage variable resistor includes a structure which makes it possible to achieve stable and reliable contact conduction between a connection terminal 7 and a terminal electrode 2a. The connection terminal 7 includes a spring portion 7b. At the end of the spring terminal 7b there is provided a flat contact section 7d which is wider than the other portions thereof. A plurality of protrusions 7e, 7f are formed on this contact section 7d. The outer edge portion of a lead line connecting section 7a of the connection terminal 7, which is accommodated in and fixed to a connection terminal accommodating section 6, is held in a terminal holding groove 6a of the connection terminal holding section 6, and the protrusions 7e, 7f are held in contact with the terminal electrode 2a of an insulating substrate 2 and pressed against the insulating substrate 2.

Abstract: Recent UV-lithography is required to provide a fine and sharp pattern with a line width of 0.5 .mu.m or less. A silica glass member adapted for use as an optical element for UV-lithography, by giving consideration to the RMS value of wave front aberration and the slant element of refractive index, which have not been considered in the art. Also there is provided a silica glass member excellent in durability to the ultraviolet irradiation, by introduction of hydrogen molecules at the synthesis of the silica glass, instead of using a secondary treatment for hydrogen introduction.

Abstract: Recent UV-lithography is required to provide a fine and sharp pattern with a line width of 0.5 .mu.m or less. The present invention provides a silica glass member adapted for use as an optical element for UV-lithography, by giving consideration to the RMS value of wave front aberration and the slant element of refractive index, which have not been considered in the art. Also, there is provided a silica glass member excellent in durability to the ultraviolet irradiation, by introduction of hydrogen molecules at the synthesis of the silica glass, instead of using a secondary treatment for hydrogen introduction.

Abstract: An adhesive composition enhanced in initial adhesion strength which comprises (A) an .alpha.-cyanoacrylate ester, (B) at least one chosen from aliphatic polyols and their derivatives and polyethers and their derivatives and (C) at least one chosen from aromatic polyols and their derivatives and carboxylic acids and their derivatives.

Abstract: An adhesive composition which comprises an .alpha.-cyanoacrylate compound with a certain ester ether compound and, preferably, a polyhydroxybenzoic acid compound. The composition is enhanced in heat shock resistance and improved in initial adhesion rate.