Specification for appearance inspection of optical lenses (below)

After a long study of optical lenses, the optical lens manufacturers have summed up a complete set of standard standards for the inspection of the lens appearance of the telescope. The purpose is to ensure that the appearance of each optical lens can conform to the manufacturer's standard.

Examination methods:

(1) perspective method: the lens is placed 3 centimeters below the tetragonal hole before the light source and slightly tilted.

(2) reflection method: the lens is placed on the table under the light, and the inspection method of the lens is slightly shaken before and after. Regardless of perspective or reflection method, the tested surfaces are facing the inspector.

Scratch criteria:

(1) only the largest scar: L = = 1/4 * D acceptable.

(2) at the same time, there are the biggest wounds and minor scars: L = = (W/N) x L] less than 1/2 * D acceptance.

(3) only minor injuries: L '= [(W/N) * L] less than D permission to receive L' = the total length W= scar width N= required for the scar size L= this level of scar length D= lens surface straight mirror

(4) EX.1: a lens with a specification of 80/50 and a lens diameter 40mm. After examining the surface of the lens, the scar is found to be as follows: 8mm L '=8mm < =8mm < 1/4 x > 40=10mm= > to receive EX.2: after the lens surface of 80/50 lens diameter 8.2mm, the wound marks are as follows: No. 80 wound 8mm, 60 scar, 40 40 The scar 6mm L '= (80/80) * 8 + (60/80) x 4 + (40/80) x 6=14mm < < 1/2 x 40=20mm = > EX.3: a lens with a specification of 80/50 and a lens diameter 40mm. After examining the surface of the lens, the scar is found as follows:

50 highlights 0, 40 highlights 2, 20 highlights 5

N '= (50/50) * 0 + (40/50) + 2 + (20/50) * 5=3.6 < 2 * (40/20) =4 = > tolerance (4) after coating, the highlight on the film is based on the specifications of the scratch / bright spot of the drawing

(5) when calculating equivalent luminescent spots, the bright spots from 0.002mm to 0.005mm can be ignored.

Simple conversion table:

(1) scar (Scratch) maximum scar, scar, mark, 120, 80, 60, 40, 20, 10, 120, 1/4D, 1.5D, 3.0D 6.0D 12.0D 80 1/4D 1.3D 2.0D 4.0D 8.0D 60

(2) the bright spot (Dig) diameter (mm) allows the maximum number of bright points to receive the maximum number of brightness points 0-2012 20-4024 40-6036 60-8048 80-100510 100-120612 120-140714