Abstract: A high-speed optical amplifier is considered to be an important optical device because of an increasing demand of routing, which is accompanied by an increase in complexity of networks. It is difficult to satisfy a response performance by related-art techniques, and there has been a problem in achieving a high-speed response performance of 10 microseconds or less. An optical amplifier according to the present invention includes: an input monitor means 500; an optical amplification means 310 including an optical amplification medium 300, and a control means 400 for performing feed-forward control. When the optical amplification means is controlled by the feed-forward control in response to a signal of the input monitor means 500, an overshoot signal is applied as a control signal so that a slow response performance specific to the optical amplification medium has been improved, and thereby high-speed response performance has been achieved.

Abstract: A high-speed optical amplifier is considered to be an important optical device because of an increasing demand of routing, which is accompanied by an increase in complexity of networks. It is difficult to satisfy a response performance by related-art techniques, and there has been a problem in achieving a high-speed response performance of 10 microseconds or less. An optical amplifier according to the present invention includes: an input monitor means 500; an optical amplification means 310 including an optical amplification medium 300, and a control means 400 for performing feed-forward control. When the optical amplification means is controlled by the feed-forward control in response to a signal of the input monitor means 500, an overshoot signal is applied as a control signal so that a slow response performance specific to the optical amplification medium has been improved, and thereby high-speed response performance has been achieved.

Abstract: A photoresist stripping liquid composition comprising an alkanol amine compound, a sulfone compound or sulfoxide compound, and a hydroxy compound. The composition is excellent in its photoresist stripping performance, safety and working efficiency, and does not cause corrosion on a substrate possessing a metal film.

Abstract: A cleaning composition which comprises dimethylcyclooctadienes is disclosed. There is further disclosed a method of cleaning printed circuit boards or printed wiring boards, which comprises: contacting the board with a composition comprising dimethylcyclooctadienes and 2-20% by weight of a surfactant; rinsing the board with water; and drying the board.

Abstract: A cleaning composition which comprises dimethylcyclooctadienes is disclosed. There is further disclosed a method of cleaning printed circuit boards or printed wiring boards, which comprises: contacting the board with a composition comprising dimethylcyclooctadienes and 2-20% by weight of a surfactant; rinsing the board with water; and drying the board.

Abstract: A positive photoresist composition in the form of solution which comprises a resin soluble in an aqueous alkaline solution, a 1,2-quinonediazide derivative as a photosensitizer, and at least one anti-halation agent in amounts of about 1 to about 10 parts by weight in relation to 100 parts by weight of the resin in the composition, the anti-halation agent being selected from the group consisting of dyestuffs of specific structures.

Abstract: This invention relates to an apparatus for automatically adjusting the center-height of a mold and the like which are used for manufacturing concrete pipes characterized in comprising a supporting device which supports a mold and the like for manufacturing concrete pipes horizontally in the manner that the center of the axis of the mold moves vertically along a perpendicular line and stops it at a determined position, and a detecting device which detects the position of the mold by contacting with the outside of it and controls and stops the movement of the said supporting device when the center of the mold is placed at the determined position.