Abstract: A general-purpose novel diamond-like carbon film (DLC film) and its manufacture, and the DLC film is characterized by the following items (i) to (iv); (i) the film structure contains mainly diamond crystalline phases, and has a hydrogen content of 20 atomic %, the presence of diamond crystalline phases is confirmed by analysis by the electron diffraction method, and the diffraction peak appears at 2.theta.=43.9 by analysis by the X-ray diffraction method; (ii) the density is 1.8 g/cm.sup.3 or over; (iii) the film surface is smooth and excellent in etching resistance; and (iv) the film is chemically stable and structurally stable, and these stabilities are not deteriorated under high temperature conditions.

Abstract: There is provided a novel single-bond carbonic film, matrix of which comprises carbon atoms and which is characterized by having a peak A at 1340.+-.20 cm.sup.-1 and a peak B at 1580.+-.10 cm.sup.-1 in Raman spectrum; a value of 9.7 or more for the ratio of I.sub.A /I.sub.B between the intensity of said peak A(I.sub.A) and the intensity of said peak B(I.sub.B): and a value in the range of from 30 cm.sup.-1 to 110 cm.sup.-1 for the half band width of said peak A.

Abstract: An ultraviolet reflecting mirror comprises a substrate, a high reflection factor film provided on the substrate and having a film thickness of at least 250 .ANG. and reflecting a light beam by the surface thereof, and a group of dielectric material layers comprising one or more sets of two layers of low refractive index film and high refractive index film provided on the high reflection factor film. The low refractive index film is provided on the high reflection factor film. The optical film thickness of the high refractive index film and the low refractive index film is approximately 1/4(2n-1).lambda., where n is a natural number and .lambda. is the design wavelength and 150nm.ltoreq..lambda..ltoreq.300nm. The film thickness of at least one of the high refractive index film and the low refractive index film is 3.lambda./4.

Abstract: This specification discloses a metallic rotational polygon mirror having a metallic member formed of aluminum or an alloy thereof, a thin film formed of at least one of chromium, tungsten and nickel on the metallic member, and a thin metal film of high reflection factor formed of at least one of gold, silver and copper on the thin film. The metallic rotational polygon mirror has a high reflection factor and a strong intimate contact property between the metallic member and the thin film and between the thin films, and has excellent corrosion resistance and durability.