Renishaw RCU10, Installation And User Manual, Page: 185 / 202

G-10 Reference
For reference, the vacuum wavelength (
λ
vac
) and the wavelength in normal air (
λ
ntp
) at
101,325 Pa, 20
°
C, 50% RH, 450 ppm CO
2
(calculated as above) of the various Renishaw
laser interferometer sources are as shown below.
Note: The vacuum wavelengths should be taken as exact values, the NTP values are
rounded to nine significant figures.
Table G.1 – Vacuum wavelengths
Laser source
λ
vac
(nm)
λ
ntp
(nm)
RLE arm 1 632. 990 000 632. 818 270
RLE arm 2 632. 991 450 632. 819 719
XL-80, HS20 632. 990 577 632. 818 846
The derived (interpolated) system resolutions are also shown for reference in Table G.2.
The numbers are again rounded to nine significant figures. The numbers in bold font are
the reference values from which all the other values have been derived by using the Edlen
equations above (to go from left to right in the table), or by dividing by successive powers
of two (to go down the table).
Table G.2 – Derived system resolution
RLE ARM 1 RLE ARM 2 XL-80 and HS20
Vacuum
resolutions
(nm)
NTP
resolutions
(nm)
Vacuum
resolutions
(nm)
NTP
resolutions
(nm)
Vacuum
resolutions
(nm)
NTP
resolutions
(nm)
632.990000 632.818270 632.991450 632.819719 632.990577 632.818846
316.495000 316.409135 316.495725 316.409860 316.495289 316.409423
158.247500 158.204567 158.247863 158.204930 158.247644 158.204712
79.1237500 79.1022837 79.1239313 79.1024649 79.1238221 79.1023558
39.5618750 39.5511418 39.5619656 39.5512324 39.5619111 39.5511779
19.7809375 19.7755709 19.7809828 19.7756162 19.7809555 19.7755890
9.89046875 9.88778546 9.89049141 9.88780811 9.89047777 9.88779448