Helium Neon Laser Experimental Instrument

This experimental system is designed for the study of gas laser operation, resonant cavity characteristics, and laser mode analysis. By adjusting the laser cavity and varying the resonator length, users can observe changes in laser modes and gain practical experience in laser alignment and optimization.

Using a confocal scanning interferometer, the system enables measurement of laser beam divergence and direct observation of transverse and longitudinal mode distributions. The experiment helps strengthen understanding of laser resonators, mode formation, and spectral characteristics through hands-on investigation.

• Gas laser operation and alignment
• Resonant cavity adjustment
• Laser mode analysis
• Transverse mode observation
• Longitudinal mode observation
• Beam divergence measurement
• Spectral distribution analysis
• Laser resonator studies

Optical Rail :

• Precision aluminum alloy guide rail, length 1 m

Laser Source :

• Semi-external cavity design with polarization control element, wavelength 632.8 nm, output power ≥ 1.5 mW

Scanning Interferometer :

• Concave mirror radius of curvature: 20.56 mm
• Mirror reflectivity: 99%
• Finesse constant: > 100
• Free spectral range: 3.75

Control Generator :

• Continuously adjustable voltage: 0–250 V
• DC bias output: 0–250 V
• Output frequency: 20–50 Hz

Optical Power Meter :

• Measurement range: 2 μW–200 mW
• Six selectable measurement ranges
• 3½-digit digital display

Adjustable Slit :

• Adjustment range: 0–2 mm
• Resolution: 0.01 mm

Optional Accessories

• Oscilloscope