Optical lens surface appearance testing standards

I. Definition:

Surface defects Standard: according to US military standard MIL-O-13830B represents the surface defect size with two sets of figures. For example 40/20 (or 40-20) former scratches limit the size, which limits the size of pitting.

Michiko, bright road, wounds, scratches are collectively referred to as scratches.

Spots, pits, ideas are called pitting.

Predetermined length and width ratio greater than 4: 1 is scratch; length and width ratio of less than 4: 1 is pitting.
When the different regions of the surface finish requirements are not the same element, the equivalent diameter to calculate areas: high surface quality in the region within the area equivalent diameter subject (such as the effective aperture area), low quality outer surface area calculating the equivalent diameter of the whole device.

Scratch:

US military standard "MIL-O-13830" scratches the surface of a model quality levels as the number of scratches than the standard. (NOTE: US standard unit of measurement is not specified in the scratch that is undetermined width and depth of the scratch, only to actual observed patterns as the standard.)

Here is the number of scratches Series No. usual scratches, Standard Edition sample # 10, # 20, # 40, # 60, # 80 5 level.

1. When the element is more than scratches scratch series series surface quality requirements, components failed.

For example: the surface quality requirements for the elements 60-40, represents the scratch element must ≤60 #, if there are elements> # 60 scratches, the element failed.

2. When the element does not exceed the number of stages scratches the surface quality requirements of the series, but there is a maximum element scratches, all the maximum length of the scratches should not exceed 1/4 of the diameter of the element.