BS78Laserscale

Features
Specifications
Dimensions
Manual
Catalog

Features

High-speed and high-resolution, while maintaining stable, ultraprecision measuring. Ideal for precision stages, semiconductor inspection/manufacturing systems, and ultraprecision processing machines.

High-resolution scale with signal pitch of approx. 138nm, outperforming light wave interferometer systems
High stability, unaffected by humidity, air pressure and air disturbances
Reference point accuracy : ±0.1μm
Scale accuracy : ±0.04μm (measuring length : 40 mm)
Non-contact design eliminates return error.
Special non-magnetic and vacuum-compatible models available
Using low expansion glass : -0.7 x 10^-6/℃ (measuring length : 10 to 420 mm)

Specifications

Specifications
Magnescale reserves the right to change product specifications without prior notice.
Model	BS78
Measuring length	10(only N/NS)/40/70/120/170/220/270/320/370/420
Overall length	58mm (L=10mm:open type scale), L + 26mm (L= 40mm to 420mm) L: Measuring length
Max. travel	L + 2mm (L=10mm:open type scale), L +10mm (L= 40mm to 420mm) L: Measuring length
Scale accuracy(at 20˚C)	NS type, RS type : ±0.03μm (L=10mm : NS type) ±0.04μm (L=40mm) ±0.10μm (L=70/120mm) ±0.18μm (L=170/220mm) ±0.25μm (L=270mm) ±0.34μm (L=320mm) ±0.39μm (L=370mm) ±0.44μm (L=420mm) L: Measuring length	N type, R type : ±0.06μm (L=10mm : N type) ±0.08μm (L=40mm) ±0.20μm (L=70/120mm) ±0.35μm (L=170/220mm) ±0.50μm (L=270/370mm) ±0.65μm (L=420mm) L: Measuring length
Grating pitch	Approx. 0.55μm
Signal pitch	Approx. 0.138μm (Approx. 138nm)
Reference point accuracy	0.1μm (Only R/RS type)
Reference point position	At the center, and every 50mm from the center to the left and to the right (BS78 models with measuring lengths of 320, 370, 420mm: 20mm offset from the center at 50mm intervals)
Reference point detection direction	Single direction
Return error	This is virtually eliminated. It should be considered to be less than two resolution limits of the detector that is used.
Repeatability	This is virtually eliminated. It should be considered to be less than one resolution limit of the detector that is used.
Thermal expansion coefficient	-0.7×10^-6/℃
Light source	Semiconductor laser : Wavelength 790nm, Output 6mW
Radiation power	DHHS class 1
Detection principle	Diffraction grating scanning system
Operating temperature	10 to 30˚C (No condensation)
Storage temperature	-10 to 50˚C (Humidity 60% or less)
Max. response speed	400mm/s (When connected with BD96)