HeNe Laser Systems
HeNe laser system is a gas laser with helium (He) and neon (Ne) as the gain medium. It has the characteristics of high stability, excellent beam quality, and low power output, and is widely used in scientific research, industry, and medical fields.
1. What are the Structural Composition of HeNe Laser Systems?
Laser Tube: A sealed glass tube containing a helium-neon mixed gas (ratio 5:1 to 20:1), which excites the population inversion through high-voltage discharge.
Resonant Cavity: It is composed of a high-reflectivity plane mirror and an output coupling mirror with a transmittance of about 1%, supporting laser oscillation of a specific wavelength.
Power Module: Provides stable high-voltage discharge to maintain the ionized state of the gas.
2. What are the Core Parameters of HeNe Laser Systems?
Wavelength: The main wavelength is 632.8nm (red light), and other wavelengths include 543nm (green light), 1.15μm, 3.39μm, etc.
Output Power: 0.3mW to 100mW (typical value), the power is limited by the characteristics of the gain medium.
Beam Characteristics: excellent monochromaticity (Δν<20Hz), high directivity (divergence angle<1mrad), coherence length of about 30cm.
3. What are HeNe Laser Systems Used for?
Precision Measurement: used for interferometers, metrology calibration, and optical instrument alignment.
Biomedical: supports flow cytometry, confocal microscopy, and medical equipment imaging.
Industrial Detection: used in food sorting, clean room monitoring, and material opacity analysis.
4. What are the Technical Features of HeNe Laser Systems?
Frequency stabilization design: some models integrate frequency stabilization technology (such as the 25-STP series) to improve frequency stability.
Low maintenance cost: simple structure, no complex cooling system required, suitable for long-term stable operation.
Multi-wavelength extension: by adjusting the resonant cavity design, it can support infrared and visible light multi-band output.
With its mature technology and reliability, the HeNe laser system occupies an important position in low-power continuous laser demand scenarios.
HeNe Laser Systems FAQs
1) What are the wavelength characteristics of HeNe lasers?
HeNe lasers typically output red light (632.8 nanometers), which is in the visible light range and is highly monochromatic and coherent. Similar wavelength stability is also used in other laser types (such as fiber lasers) for high-precision marking and industrial detection.
2) How to maintain the stability of HeNe laser systems?
Maintenance requires attention to environmental temperature and humidity control, avoidance of vibration interference, and regular calibration of optical components. Maintenance recommendations for industrial laser equipment (such as laser trackers) include software updates and hardware cleaning to ensure long-term accuracy.
3) What is the difference between HeNe lasers and other gas lasers?
Compared to CO₂ or argon ion lasers, HeNe lasers have lower power but higher stability, making them suitable for non-destructive applications. Similar comparisons can be seen in the selection of fiber lasers and UV lasers in the processing of different materials.
4) How safe is the HeNe laser system?
Class 3B laser safety standards must be followed, protective glasses must be worn, and direct exposure to human eyes or skin must be avoided. The operating specifications of other industrial laser equipment (such as welding systems) also emphasize safety training and equipment shielding.
5) What are the cost factors of HeNe laser systems?
The initial purchase cost of HeNe lasers is moderate, but additional investment in calibration equipment (such as laser trackers) and environmental stabilization devices is required. Long-term maintenance costs include regular replacement of gas mixtures (such as helium-neon mixed gases) and optical component cleaning services.
6) What are the main differences between HeNe lasers and fiber lasers in industrial applications?
HeNe lasers: The advantages are low noise and high coherence, which are suitable for precision measurement and laboratory-level calibration.
Fiber lasers: Higher power (up to kilowatt level), suitable for high-intensity processing such as metal welding and cutting. The two are often used in complementary ways in material processing.
7) Does the HeNe laser system need to be calibrated regularly? How long is the calibration cycle?
Yes. For example, in machine tools or three-dimensional coordinate measuring machines, it is recommended to calibrate once every 6-12 months using a laser tracking interferometer to ensure that the geometric error is less than 1 micron. Some high-precision scenarios (such as aerospace manufacturing) need to be shortened to 3 months.
8) What is the recommended protective equipment for HeNe lasers?
Basic protection: Class 3B laser protective glasses (for 632.8 nm wavelength).
Industrial scenarios: A shielding cover or optical path closure device is required to prevent the hazards of scattered light. Some automated systems (such as laser welding equipment) can integrate safety interlock functions.
9) What are the cutting-edge applications of HeNe lasers in scientific research?
Optical detection: Used for laser-induced damage threshold (LIDT) testing to evaluate the stability of materials under high-energy beams.
Nanomanufacturing: Combined with interference technology, etching and detection of submicron structures can be achieved.