Laser Transverse Mode Teaching System
Knowledge Points Involved:Cat's-eye Resonator Adjuster, Optical Resonator and Its Characteristics, Laser Polarization State, Laser Transverse Modes, Rectangular Transverse Modes, Circular Transverse Modes, High-Order Transverse Modes, and Transverse Mode Transformation.
Laser Transverse Mode Teaching System Structure Diagram
Courses Involved:
Optics, laser principles, laser optics, optoelectronics, laser technology, etc.
Experimental Content:
Resonant cavity adjustment
Adjustments and transformations in the transverse mold mode.
Study on the transverse mode polarization characteristics of laser output
Observation of high-order rectangular cross-section molds, high-order circular cross-section molds.
e Determination of m and n values in the transverse model TEMmn.
Experimental Principle Diagram:
Cat Eye Damper Regulator, featuring a concave mirror (HR@632.8nm) and a convex lens (AR@632.8nm), with the concave mirror having a radius of curvatureRThe focal length of the convex lens isfTwo-mirror spacingLWhenf=R=LAt the time, the cat's eye cavity damage regulator equivalent
For a flat mirror; whenL<f=RAt that time, the cat's eye cavity damage regulator is equivalent to a convex mirror; whenL>f=RAt that time, the cat's eye cavity loss regulator is equivalent to a concave mirror.
Resonant cavity diagram
Adjust the resonator loss using a lens assembly, altering the loss of the resonator for different transverse modes. Oscillations of the transverse modes with lower loss are allowed, while those with higher loss are suppressed.
Experimental Effect Image:
Available for demonstration fromTEM00MoldTEM22Mode mold even higher-order cross-mode mode
Technical Specifications:
Half-external cavity helium-neon laser module: central wavelength 632.8nm, gain tube length 250mm, concave mirrorROutput: 1m, capillary length 200mm, inner diameter of capillary 2.0mm, laser cavity length about 290mm.
Output Expansion Componentf30mm concave lens.
Equipment completeness:
HeNe extranuclear laser module, cat's eye cavity loss adjuster module, polarizer module, receiving light screen.
Usage Instructions:
1. Power On/Off: This system operates on 220V AC power. After plugging in, press the red button on the laser power supply. The glow from the laser tube is normal. At this point, you can adjust the resonant cavity output laser with the cat's eye cavity loss regulator. To turn off the system, simply press the red button on the laser power supply again. The operation is easy and convenient.
The Cat Eye Cavity Damage Adjuster is controlled by five adjustment knobs: horizontal, vertical, pitch, yaw, and fore-aft. After the laser outputs its laser beam, these five knobs can be adjusted to produce different transverse mode patterns.
3. Routine Maintenance: After using the horizontal mold teaching system, cover the entire set of equipment with a glass cover to prevent dust. If the laser output power cannot be adjusted after some time, it may be due to dust on the exposed mirror in the cat's eye cavity adjuster and the window pane near the laser tube being covered in dust. Simply wipe these two mirrors with alcohol swabs.
Suggested Class Hours:
1 lesson, or teaching配套demonstration.
