< Back to News

Explanation of optical drawing standard ISO 10110

30th Jun 2020

Read our July 2020 newsletter. 

Explanation of optical drawing standard ISO 10110

Optical drawings can sometimes be very confusing unless you are familiar with some of the shorthand terminology that is commonly used. The ISO standards allow us to communicate effectively and provide a lot of information without taking up too much room on the drawing. Here is an example drawing and a helpful break down for some of the more frequently used notation: 

Left Surface Material Right Surface
R1 -42.00mm CC CaF2 R2 42.00mm CX
⌀ 36.00mm 0/ 10 ⌀ 36.00mm
Chamfer: 0.2-0.5mm 1/ 5x0.1 Chamfer: 0.2-0.5mm
AR coated R < 0.5% 1064nm 2/ 1; 2 AR coated R < 0.5% 1064nm
3/ 5(0.5/2); 632nm   3/ 5(0.5/2); 632nm
4/ 6’   4/ 6’
5/ 5x0.3; C3x0.4; L3x0.02; E0.5   5/ 5x0.3; C3x0.4; L3x0.02; E0.5

0/ Stress birefringence                 
“0/ A” where A is the maximum allowable stress in nm/cm of optical path length in the sample material. (e.g. 0/ 10)

1/ Bubbles and inclusions            
“1/ NxA” where N is the number of bubbles or inclusions of maximum permitted size in the material, and A is the measure of their size in mm, equal to the square root of the projected area of the largest permissible bubble and/or inclusion in mm. (e.g. 1/ 5x0.1)
 
2/ Inhomogeneity and striae     
"2/ A; B" Inhomogeneity is a gradual variation of index within an element. Striae is the term for inhomogeneities having a small spatial extent. Both parameters are categorized in terms of a class. (e.g. 2/ 1; 2)

 

3/ Surface form tolerances         
“3/ A(B/C)”, (e.g. 3/ 5(0.5/2); 632nm)
A = maximum power deviation (peak to valley) from a test plate in fringe spacings
B = maximum value of irregularity (peak to valley) in fringe spacings
C = maximum value (peak to valley) of rotationally symmetric irregularity in fringe spacings (rarely used)
 
4/ Centering tolerances                  
“4/ σ” defined as the maximum tilt angle at the datum axis in minutes (‘) or seconds (“) of arc. (e.g. 4/ 6')
 
5/ Surface imperfections             
“5/ NxA; CN’xA’; LN”xA”; EA’’’, (e.g.5/ 5x0.3; C03x0.4; L3x0.02, E0.5)
NxA = number of allowed surface imperfections where A is the square root of the area of maximum allowed imperfection in mm
CN’xA’ = number of allowed coating blemishes of maximum size where A is the leg length of a sample square in mm
LN”xA” = number of allowed long scratches where A” is the maximum allowed width of scratches over 2mm, expressed in mm
EA’’’ = edge chips where A’’’ is the maximum inward extent of the chip in mm
 


Surface texture                                                               
“Rq 0.05-2 G√ 5” indicates a ground surface with Rq between 0.05 – 2 microns with minimum sample length of 5mm. Often you might see a polished surface classified as:

Level of polishing Number of defects per 10mm linear scan of surface Approximate roughness (nm)
P1 80 < N < 400 < 8
P2 16 < N < 80 < 4
P3 3 < N < 16 < 2
P4 N < 3 < 1

Table of permissible deviations and material imperfections in case these parameters are not given:


 
Note: This data is intended as practical advice only.
Crystran Ltd cannot be responsible for any repercussions caused as a result of using this data.
The full ISO 10110 standards can be downloaded from the ISO website: https://www.iso.org/standard/57574.html


We hope you find this information helpful, and please let us know if you have any suggestions for future newsletter topics.

Related