OPTICAL TEST FLAT SURFACE Bottom PLATE LZOS 60x21mm/2.4x0.83inch+LOG+BOX

Description

PRECISION OPTICAL 1/12 Wave Test FLAT SURFACE Bottom PLATE
60x21mm/2.4x0.83inch
GLASS FOR INSPECTION
+LOG+BOX
LZOS USSR RUSSIA
This is an optical surface plate for inspection.
Condition - unused.
Best condition !
Diameter of the plate:
6.0 cm./2,4inch.
Thickness:
2.1 cm./0.83 inch.
Serial number:
7417
Deviations of flatness of the working surface:
0.07 micron
Local deviations of flatness of the working surface:
0.02 micron
The material of this plate is glass of Soviet /Russian brand
K8 GOST
(State All-Union standard USSR State standard specification) 3514-76 .
The plate was made by the famous production association
"Rubin"
in
Lytkarino
(a town near Moscow) in
1972.
There is a brand label of this factory on the surface of the plate.
There is also a Soviet high-quality sign
"Pentagonal"
with a Russian letter
"K"
(
"K"
is the first letter of the Russian word
"quality"
) and Russian inscription
"USSR".
The plate comes with an original box and log.
For Reference:
The thermal expansion coefficient of glass brand
K8
:
7.1x10-6
degrees Celsius
in the range of -30
+
70 degrees Celsius.
8.3x10-6/
degrees Celsius
in the range of +20
+300
degrees Celsius.
For comparison, coefficient of thermal expansion of quartz is about
0.55x10-6/degrees Celsius
in the range
(+20+320 degrees Celsius).
Supported payment method:
PayPal. Please,
submit PayPal payments.
Shipping conditions:
All items will be shipped using Air Mail. Shipping price is the same worldwide.
Bidding conditions:
We reserve the right to cancel all bids from members will less than 10 feedback rating.
We offer a free gift for each buyer.