Abstract: A process for producing a synthetic silica glass optical component which contains at least 1×1017 molecules/cm3 and has an OH concentration of at most 200 ppm and substantially no reduction type defects, by treating a synthetic silica glass having a hydrogen molecule content of less than 1×1017 molecules/cm3 at a temperature of from 300 to 600° C. in a hydrogen gas-containing atmosphere at a pressure of from 2 to 30 atms.

Abstract: A connector component for optical fibers has good dimensional accuracy and parallelism. The connector component includes a base material. The base material is provided with at least two holes for inserting and fixing optical fibers therein. The base material is made of quartz glass. Inner components are arranged for forming holes for inserting optical fibers in a die for forming an outer form of the connector component with a dimensional accuracy equal to or less than 2 ?m. Slurry is poured into the die, the slurry including quartz powder, a resin binder, a dispersant, water and a curing agent. The poured slurry is cured and heated under vacuum so as to vitrify the cured slurry to obtain the quartz glass.

Abstract: A connector component for optical fibers has good dimensional accuracy and parallelism. The connector component includes a base material. The base material is provided with at least two holes for inserting and fixing optical fibers therein. The base material is made of quartz glass. Inner components are arranged for forming holes for inserting optical fibers in a die for forming an outer form of the connector component with a dimensional accuracy equal to or less than 2 ?m. Slurry is poured into the die, the slurry including quartz powder, a resin binder, a dispersant, water and a curing agent. The poured slurry is cured and heated under vacuum so as to vitrify the cured slurry to obtain the quartz glass.

Abstract: There is provided a multi-cored fiber array for optical communication which has high dimensional accuracy, can easily be prepared by machining, and is low in cost. There is also provided a fiber array for optical communication which can reduce the necessary amount of an adhesive used for fixing optical fibers to a substrate. The fiber array for optical communication comprises: a substrate for inserting optical fibers therein; and a press plate for pressing and fixing the inserted optical fibers. The substrate has a plurality of grooves into which the optical fibers are to be inserted. The accuracy of the center-to-center dimension between the grooves adjacent to each other is within ±0.5 ?m, and the degree of parallelization in the groove length direction between the grooves adjacent to each other is within ±0.1 degree.

Abstract: A connector component for optical fibers has good dimensional accuracy and parallelism. The connector component includes a base material. The base material is provided with at least two holes for inserting and fixing optical fibers therein. The base material is made of quartz glass. Inner components are arranged for forming holes for inserting optical fibers in a die for forming an outer form of the connector component with a dimensional accuracy equal to or less than 2 ?m. Slurry is poured into the die, the slurry including quartz powder, a resin binder, a dispersant, water and a curing agent. The poured slurry is cured and heated under vacuum so as to vitrify the cured slurry to obtain the quartz glass.

Abstract: A synthetic quartz glass for optical use, to be used by irradiation with light within a range of from the ultraviolet region to the vacuum ultraviolet region, which contains fluorine, which has a ratio of the scattering peak intensity of 2250 cm?1 (I2250) to the scattering peak intensity of 800 cm?1 (I800), i.e. I2250/I800, of at most 1×10?4 in the laser Raman spectrum, and which has an absorption coefficient of light of 245 nm of at most 2×10?3 cm?1.

Abstract: There is provided a multi-cored fiber array for optical communication which has high dimensional accuracy, can easily be prepared by machining, and is low in cost. There is also provided a fiber array for optical communication which can reduce the necessary amount of an adhesive used for fixing optical fibers to a substrate. The fiber array for optical communication comprises: a substrate for inserting optical fibers therein; and a press plate for pressing and fixing the inserted optical fibers. The substrate has a plurality of grooves into which the optical fibers are to be inserted. The accuracy of the center-to-center dimension between the grooves adjacent to each other is within ±0.5 ?m, and the degree of parallelization in the groove length direction between the grooves adjacent to each other is within ±0.1 degree.

Abstract: An optical connector capable of providing a multicore ferrule for optical communication or a fiber array for optical communication having a high dimensional accuracy and easily manufactured at a low cost, comprising a plurality of insert holes for inserting optical fibers therein arranged at specified intervals, characterized in that the accuracy of the center-to-center distances between the adjacent insert holes is within ±0.5 ?m and a parallelism between the adjacent insert holes in hole axial direction is within ±0.1°.

Abstract: A synthetic quartz glass for optical use, to be used by irradiation with light within a range of from the ultraviolet region to the vacuum ultraviolet region, which contains fluorine, which has a ratio of the scattering peak intensity of 2250 cm−1 (I2250) to the scattering peak intensity of 800 cm−1 (I800), i.e. I2250/I800, of at most 1×10−4 in the laser Raman spectrum, and which has an absorption coefficient of light of 245 nm of at most 2×10−3 cm−1.

Abstract: A connector component for optical fibers has good dimensional accuracy and parallelism. The connector component includes a base material. The base material is provided with at least two holes for inserting and fixing optical fibers therein. The base material is made of quartz glass. Inner components are arranged for forming holes for inserting optical fibers in a die for forming an outer form of the connector component with a dimensional accuracy equal to or less than 2 &mgr;m. Slurry is poured into the die, the slurry including quartz powder, a resin binder, a dispersant, water and a curing agent. The poured slurry is cured and heated under vacuum so as to vitrify the cured slurry to obtain the quartz glass.

Abstract: An exposure apparatus, wherein at least one of optical members constituting an exposure light source system, an illuminating optical system, a photomask and a projection optical system, is made of a synthetic quartz glass for an optical member, which has an absorption coefficient of 0.70 cm−1 or less at a wavelength of 157 nm and an infrared absorption peak attributable to SiOH stretching vibration at about 3640 cm−1.

Abstract: A synthetic quartz glass to be used for light with a wavelength of from 150 to 200 nm, wherein the OH group concentration is at most 100 ppm, the hydrogen molecule concentration is at most 1×1017 molecules/cm3, reduction type defects are at most 1×1015 defects/cm3, and the relation between &Dgr;k163 and &Dgr;k190, as between before and after irradiation of ultraviolet rays, satisfies 0<&Dgr;k163<&Dgr;k190, and a process for its production.

Abstract: A process for producing a synthetic quartz glass for an optical member, which comprises a step of irradiating a synthetic quartz glass having an OH group content of 50 ppm or lower with vacuum ultraviolet light having a wavelength of 180 nm or shorter to improve the transmittance in a region of wavelengths of not longer than 165 nm.

Abstract: A process for producing a synthetic silica glass optical component which contains at least 1×1017 molecules/cm3 and has an OH concentration of at most 200 ppm and substantially no reduction type defects, by treating a synthetic silica glass having a hydrogen molecule content of less than 1×1017 molecules/cm3 at a temperature of from 300 to 600° C. in a hydrogen gas-containing atmosphere at a pressure of from 2 to 30 atms.

Abstract: A synthetic quartz glass for optical use, to be used by irradiation with light within a range of from the ultraviolet region to the vacuum ultraviolet region, which contains fluorine, which has a ratio of the scattering peak intensity of 2250 cm−1 (I2250) to the scattering peak intensity of 800 cm−1 (I800), i.e. I2250/I800, of at most 1×10−4 in the laser Raman spectrum, and which has an absorption coefficient of light of 245 nm of at most 2×10−3 cm−1.