The surface roughness (Rz) is a ten-point average roughness.

The surface roughness Ra(b) and the surface roughness Ra(i) are arithmetical mean roughness values and are surface roughness parameters determined in accordance with a Germany standard "DIN-4768".

The surface roughness of the haptic zone may be greater than the surface roughness of the optic zone.

The preliminary average surface roughness is less than the final average surface roughness.

The back (100a) of the substrate of the InGaAs laser is processed into an optically irregularly reflecting face having a continuous irregularity the surface roughness (Rq: root mean square roughness) of which is 100 nm.

Surface coarseness of the workpiece surface is determined on the basis of the relative roughness relationship described above.

The roughnesses R1 and R2 are smaller than at least one of the roughnesses R3 and R4.

The roughness of the second layer corresponds to the roughness of the first layer, where the first layer has a roughness greater than or equal to about 20 Å root mean square (RMS).

Roughness of tissue is characterized by Average Primary Amplitude and Average Peak to Valley Waviness.

The roughening can occur in two steps.

Wheel and rail roughness

The roughness of the slide surface of the shaft is preferably 0.2 μm or greater in arithmetic average roughness.

  In arithmetic mean roughness (Ra) of the side face, the arithmetic average roughness (Ra2) of the continuous groove worked surface is smaller than the arithmetic average surface roughness (Ra1) of the broken portion surface.

As a result, there can be accomplished an improvement of surface roughness to thereby enable obtaining of a desirable surface roughness.

improving grip/roughness of pavements