Laser Heads

The EXCEL PRECISION 1001 Laser Head series is a two-frequency Helium-Neon Laser System designed specifically for use with optical interferometers and associated detection and optics hardware. The primary use for the 1001 Laser Head is in the following equipment: wafer /FPD steppers, E-beam machines, I.C. inspection products, backend steppers, precision measuring machines, and ultra-precision machine tools.

Laser frequency stability is achieved by utilizing the principle of the Zeeman effect. A longitudinal magnetic field is applied to the laser tube, which causes the atomic level of neon to split into two energy levels. The frequencies of these two levels are essentially equally spaced about the center wavelength and are shifted proportional to the applied magnetic field strength. The laser tube therefore, is lasing at two frequencies with a frequency difference proportional to the magnetic field strength. These two frequencies are separated symmetrically with respect to the original frequency generated before the magnetic field is applied. Extremely high accuracy and repeatability can be achieved during measurement.

The high split frequency for Excel 1001 Laser Head allows the measurement speed to reach 1.0 m/sec (resolution dependent). It is compatible to all Excel optical products and can support up to 6 axes of measurement (6/ea. Interferometers and 6/ea. Receivers).

Power Requirements 2.5A @ 15V DC (Start up)
   1.1A @ 15V DC (Operating)
Split Frequency (Excel can provide custom split frequency at request) 1.6 – 1.9 MHz (1001F), 2.4 – 3.0 MHz (1001C), 3.4 – 4.0 MHz (1001D)
Vacuum Wavelength 632.99137 nm (nominal)
Frequency Stability  2 x 10 ^-8 (nominal)
Pointing Stability < 0.1 x 10 ^-3 radians after fully warm up
Beam Diameter  6 mm typical (3mm & 9mm optional)
Laser Power Output > 0.2 mW ; < 1 mW
Dimensions 35 x 13 x 11.5 cm
Signal Output Differential square wave
Measuring Speed (model dependent Up to 1.0 m/sec with linear interferometer

1001A front and rear panels

1001C/1001D/1001F front and rear panels

1001C_D_F with vent

Laser head models with /without vent holes

Excel Precision manufactures laser headsof three sizes. Model 1001A/1001C/1001D/1001F are equal in size, and have a smaller footprint than the 1001B or 1101A. Mechanical variations of these are available on special order.

Model Max. Speed
 1001A 0.6 m/sec
1001B 0.6 m/sec
1001C 0.8 m/sec
1001D 1.0 m/sec
1001F 0.6 m/sec
1101A 0.6 m/sec

1001A/1001C/1001D/1001F laser head dimensions (mm)

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