An optical recording medium includes a light-receiving surface that receives incident light and at least three information signal layers on which information signals are to be optically recorded. Among the at least three information signal layers, the information signal layer closest to the light-receiving surface has a reflectance in a range of 4% to 11%.

A light detection and ranging (LiDAR) system is provided including a beam steering device configured to modulate a phase of light from a light source and to output light in a plurality of directions at the same time, a receiver including a plurality of light detection elements configured to receive light that has been irradiated onto an object in the plurality of directions from the beam steering device and reflected from the object, and a processor configured to analyze position-specific distribution and/or time-specific distribution of light received by the receiver and to individually process the light lights irradiated onto the object in the plurality of directions.

An optical recording medium includes a reflective layer, a first dielectric layer, a phase-change recording layer, and a second dielectric layer. The phase-change recording layer has an average composition represented by SbxInyMz, in which M is at least one of Mo, Ge, Mn, and Al, and x, y, and z are values in the ranges 0.70x0.92, 0.05y0.20, and 0.03z0.10, respectively, provided that x+y+z=1, the first dielectric layer includes a zirconium oxide-containing composite material or tantalum oxide, and the second dielectric layer includes a chromium oxide-containing composite material or silicon nitride.

An optical recording medium includes a reflective layer, a first dielectric layer, a phase-change recording layer, and a second dielectric layer. The phase-change recording layer has an average composition represented by SbxInyMz, in which M is at least one of Mo, Ge, Mn, and Al, and x, y, and z are values in the ranges 0.70x0.92, 0.05y0.20, and 0.03z0.10, respectively, provided that x+y+z=1, the first dielectric layer includes a zirconium oxide-containing composite material or tantalum oxide, and the second dielectric layer includes a chromium oxide-containing composite material or silicon nitride.

An optical recording medium includes a plurality of information signal layers, and at least one of the plurality of information signal layers other than the farthest information signal layer from a light irradiation surface includes: a recording layer; a first dielectric layer provided on a side opposite to a light incident side of the recording layer; and a second dielectric layer provided on the light incident side of the recording layer. The first dielectric layer and the second dielectric layer include indium oxide and tin oxide, and the atomic concentration of tin in the first dielectric layer is higher than the atomic concentration of tin in the second dielectric layer.

An optical recording medium includes a plurality of information signal layers, and at least one of the plurality of information signal layers other than the farthest information signal layer from a light irradiation surface includes: a recording layer; a first dielectric layer provided on a side opposite to a light incident side of the recording layer; and a second dielectric layer provided on the light incident side of the recording layer. The first dielectric layer and the second dielectric layer include indium oxide and tin oxide, and the atomic concentration of tin in the first dielectric layer is higher than the atomic concentration of tin in the second dielectric layer.

An optical recording medium includes a plurality of information signal layers on which information signals are to be optically recorded. Among the plurality of information signal layers, the information signal layer closest to the light-receiving surface has a reflectance of more than 4%.

An optical recording medium includes a plurality of information signal layers on which information signals are to be optically recorded. Among the plurality of information signal layers, the information signal layer closest to the light-receiving surface has a reflectance of more than 4%.

A sintered compact target containing an element(s) (A) and an element(s) (B) as defined below is provided. The sintered compact target is free from pores having an average diameter of 1 m or more, and the number of micropores having an average diameter of less than 1 m existing in 40000 m.sup.2 of the target surface is 100 micropores or less. The element(s) (A) is one or more chalcogenide elements selected from S, Se, and Te, and the element(s) (B) is one or more Vb group elements selected from Bi, Sb, As, P, and N. The provided technology is able to eliminate the source of grain dropping or generation of nodules in the target during sputtering, and additionally inhibit the generation of particles.

A sintered compact target containing an element(s) (A) and an element(s) (B) as defined below is provided. The sintered compact target is free from pores having an average diameter of 1 m or more, and the number of micropores having an average diameter of less than 1 m existing in 40000 m.sup.2 of the target surface is 100 micropores or less. The element(s) (A) is one or more chalcogenide elements selected from S, Se, and Te, and the element(s) (B) is one or more Vb group elements selected from Bi, Sb, As, P, and N. The provided technology is able to eliminate the source of grain dropping or generation of nodules in the target during sputtering, and additionally inhibit the generation of particles.