MI-Series
Design and Operation
Series MI miniature retroreflector interferometers are pre- cision length measuring instruments with a wide range of applications. The can be adapted geometrically and func- tionally to specific tasks.
The miniaturized sensor head and corner cube reflector enable the instrument to be used both as a permanent- ly installed measuring system as well as a transportable calibration system. The fiber-optic coupled sensor head makes the systems easy to use.
The miniature interferometer converts the measuring mo- vement of the corner cube reflector into an interference signal.
The miniature interferometer converts the measuring mo- vement of the corner cube reflector into an interference signal. This optical signal is transmitted through fiber-optic cables to the optoelectronic supply and evaluation unit, and output as a length value. The basis for the high mea- surement accuracy and linearity is achieved by using an HeNe laser as the metrological standard, and by correc- ting environmental effects on the laser wavelength.
Operation and display take place optionally on a separate display unit or on a PC with optional software.
Major Performance Features
• Flexible, ultraprecise length measuring system
• Adaptable to specific customer requirements
• Easy adjustment
• High maximum displacement speed of the measuring reflector
• Large permissible tilting of the measuring reflector
• Fiber-optic coupling of the sensor head
• No thermal effects on the measurement environment
• Not sensitive to electromagnetic fields
• HeNe laser with high frequency stability as the metrological standard
• Correction of environmental influences on the wave- length of the laser light
• Traceable to national standards
• The sensor head may be made of aluminum, stainless steel or invar
• Data acquisition and display software
• Open interfaces for OEM software under Windows and Linux
Applications
• Laser interferometric precision length measuring system for installation in single and multi-axis measu- ring tables, microscope stages, machine tools and positioning tables
• Calibration of machine tools and coordinate measuring machines
• Precision length measurements in research and deve- lopment
Technical Data
Model MI 60
Model MI 150
Model MI 5000
Measurement range (Max. distance reflector - sensor head)
mm
60
150
5000
Resolution
pm
20
20
20
Laser wavelength
nm
632.8
632.8
632.8
Frequency stability of the HeNe laser (after warm-up time)
3 · 10-7
3 · 10-7
2 · 10-8
Warm-up time of the HeNe laser
min
1
1
10...20
Operating temperature range
°C
15...30
Maximum tilting angle of measuring reflector (Center of rotation in center of reflector)
degree
±1.5
Maximum displacement speed of the measuring reflector
mm/s
800
Dimensions (L x W x H):
Sensor head with alignment base Corner
cube reflector
Optoelectronic supply and evaluation unit
mm
mm
mm
140 x 90 x 47
30 x 15 x 13
450 x 400 x 150
Mass:
Sensor head with alignment base Corner
cube reflector
Optoelectronic supply and evaluation unit
g
g
kg
800
12
ca 8
Interfaces standard optional
RS232C, USB
Digital 32-bit parallel interface Digital
incremental signals (TTL level)
Analog incremental signals (1VPP)
Cable length between sensor head and electronics unit
m
3, optionally up to 10
Line voltage / frequency
VAC/Hz
100...240 /47...60
Laser safety class according to EN 60825-1:2007 and
ANSI Z136.1 (CDRH)
2M
II