Abstract: A method and apparatus are disclosed wherein, while holding an optical fiber 1 by an optical fiber holder section 4 so as to serve a distal end 1a of the optical fiber 1 as a free end and holding the distal end 1a of the optical fiber 1 in contact with a grinding flat portion 5b to cause the distal end 1a of the optical fiber 1 to be flexed on the grinding flat portion 5b, reciprocating movement for causing the distal end 1a of the optical fiber 1 to slide on the grinding flat portion 5b in a first sliding direction and an oppositely orientated second sliding direction is relatively implemented a plural number of times between the grinding flat portion 5b and the distal end 1a of the optical fiber 1.

Abstract: A method and apparatus are disclosed wherein, while holding an optical fiber 1 by an optical fiber holder section 4 so as to serve a distal end 1a of the optical fiber 1 as a free end and holding the distal end 1a of the optical fiber 1 in contact with a grinding flat portion 5b to cause the distal end 1a of the optical fiber 1 to be flexed on the grinding flat portion 5b, reciprocating movement for causing the distal end 1a of the optical fiber 1 to slide on the grinding flat portion 5b in a first sliding direction and an oppositely orientated second sliding direction is relatively implemented a plural number of times between the grinding flat portion 5b and the distal end 1a of the optical fiber 1.

Abstract: A primary matrix pattern such as 5 .times. 7 matrix structure and an auxiliary matrix pattern such as 4 .times. 6 matrix structure are combined with each other in an ink jet system printer in such a manner that auxiliary dots contributing to the auxiliary matrix pattern are shifted in both column and row directions by a half dot position with respect to the primary matrix pattern. These auxiliary dots function to increase dot density along oblique lines in the dot matrix pattern.

Abstract: The thermal print head comprises a substrate, a semiconductor wafer fabricated thereover, a plurality of junctions formed on the semiconductor wafer, and electrodes to supply an inverse current to the junctions. The junctions are arranged so as to correspond to the pattern of the symbol, such as letters, to be printed. Each of the junctions is used as a heating element. Heat is evolved at the junction when the inverse current flows through the potential barrier which is formed at the junction. The heat evolved is used for the heating element.