Class II Diode Lasers
Last Updated: April 1, 2025
Description
Class II diode lasers are devices that emit coherent light from the edge of a semiconductor chip. They are known for their small form factor and high efficiency, allowing them to produce significant output power despite their compact size. These lasers are typically used in applications where precision and efficiency are critical.
Working Principle
Class II diode lasers operate by emitting light through the edge of a semiconductor chip, a process known as edge-emission. This design allows them to achieve high efficiency and low power requirements. The coherent light emitted by these lasers can be focused to a diffraction-limited spot size, which is dependent on the wavelength of the laser. This capability makes them useful for applications requiring precise light delivery. The ability to operate at shorter wavelengths also enhances their utility by allowing for smaller spot sizes and higher information density in optical storage applications.
Applications
Class II diode lasers are used in a variety of applications. They are commonly found in barcode readers, where they typically operate at wavelengths of 650 nm or 950 nm. In industrial settings, high-powered versions are used for welding applications, such as welding thin sheets of stainless steel or aluminum. They are also utilized in consumer electronics and medical devices, including laser pointers and diode laser hair removal systems.
Advantages over other Diode Lasers
Compared to other types of lasers, Class II diode lasers offer several advantages. They have higher efficiency than conventional gas or dye lasers and require lower power and current. Their small size and ruggedness allow them to be used in environments where other lasers cannot operate. Additionally, they can be directly modulated at high frequencies, making them suitable for high-speed data communications.
Limitations
One limitation of Class II diode lasers is their sensitivity to temperature changes. The wavelength of the laser can shift with temperature variations, which may affect performance. Additionally, the beam pointing stability can be an issue in applications requiring precise targeting over long distances.
Considerations
When considering the use of Class II diode lasers, several factors should be taken into account. Initial costs can vary depending on the specific application and power requirements. Operating expenses are generally low due to their high efficiency and low power consumption. However, maintaining the laser diode at a stable temperature is crucial for extending its lifetime, which can range from 25,000 to 50,000 hours. Proper heat management, such as using heat sinks, is recommended to prevent performance degradation. Replacement and maintenance costs are typically low, but ensuring accurate alignment and stability is important for optimal performance.
from World Star Tech
UCL Series Cross-Hair Laser modules are fully self-contained with integrated laser driver circuit, surface polished glass asherical lens optics, laser diode and cross-line generator. Unique properties include a perfectly straight cross, compact anodized aluminum body, fine adjustable focus, clean... [See More]
- CDRH Classification: Class II; Class II
- Wavelength Range: 635
- Laser Type: Laser Diodes; Laser Diode Modules
- Laser Power: 1
from Electro Optical Components, Inc.
The unique feature of this laser diode module with single mode coupling is its highly stable performance across a wide range of temperatures. The module is cooled solely using a passive system – no TEC (thermoelectric cooler) is required. Wavelengths include: 450 nm, 515 nm, 635 nm, 640 nm,... [See More]
- CDRH Classification: Class I; Class II; Class IIa; Class IIIa; Class IIIb
- Laser Wavelength: Violet; Green; Red; Infrared
- Laser Type: Laser Diodes
- Wavelength Range: 450 to 850
from World Star Tech
DPGL series green lasers are diode pumped green lasers operating at 532nm. The diode, driver and optics are integrated in a compact package. The DPGL series lasers offer excellent beam quality and stability. Modulation and beam shaping optics can be added to the DPGL series lasers. Features. [See More]
- CDRH Classification: Class II; Class II
- Laser Wavelength: Green
- Laser Type: Laser Diodes; Laser Diode Modules
- Wavelength Range: 532
from World Star Tech
ULL-Series Line Laser modules are fully self-contained with integrated laser driver circuit, surface polished glass aspherical lens optics, and laser diode. Unique properties include a compact anodized aluminum body, fine adjustable line laser, clean beam, low divergence, high boresight accuracy and... [See More]
- CDRH Classification: Class II; Class II
- Wavelength Range: 635
- Laser Type: Laser Diodes; Laser Diode Modules
- Laser Power: 1
from World Star Tech
World Star Tech offers a semi-uniform line laser at 55 deg fan angle. It is available in red and green as standard options. It is factory-focused and is a low-cost alternative to uniform line lasers with Powell Lens. These semi-uniform line lasers work well for a variety of scanning applications... [See More]
- CDRH Classification: Class II; Class II
- Wavelength Range: 635
- Laser Type: Laser Diode Modules
- Laser Power: 1 to 3.5
from World Star Tech
FLL-Series Line Laser modules are our low-cost compact line laser series for high volume alignment and positioning applications. Unique properties include a very compact rugged body (9 mm in diameter and 25 mm in length) with factory pre-focused laser line, available in a variety of fan angles. [See More]
- CDRH Classification: Class II; Class II
- Wavelength Range: 635
- Laser Type: Laser Diodes
- Laser Power: 1
from World Star Tech
ML-Series Laser modules are fully self-contained with integrated laser driver circuit, surface polished glass asherical lens optics and laser diode. Unique properties include extremely compact anodized aluminum body, collimated clean beam, low divergence, and industrial strength. TTL modulation upto... [See More]
- CDRH Classification: Class II; Class II
- Laser Wavelength: Red
- Laser Type: Laser Diodes; Laser Diode Modules
- Wavelength Range: 635
from World Star Tech
UL-Series Laser modules are fully self-contained with integrated laser driver circuit, surface polished glass aspherical lens and laser diode. Unique properties include compact anodized aluminum body, fine adjustable focus, clean beam, low divergence, high boresight accuracy and industrial strength. [See More]
- CDRH Classification: Class II; Class II
- Laser Wavelength: Red
- Laser Type: Laser Diodes; Laser Diode Modules
- Wavelength Range: 635
from World Star Tech
UT-Series Laser modules are fully self-contained with integrated laser driver circuit, surface polished glass aspherical lens optics and laser diode. Unique properties include compact anodized aluminum body, fine adjustable focus, clean beam, low divergence, high boresight accuracy and industrial... [See More]
- CDRH Classification: Class II; Class II
- Laser Wavelength: Red
- Laser Type: Laser Diodes; Laser Diode Modules
- Wavelength Range: 635
from ProPhotonix, Ltd.
The 300-0100-00 series 645nm alignment laser modules offers a range of interchangeable, pre-aligned precision optics: 88 ° cross, 58 ° line, 58 ° cross/spot, which provide optimum laser beam performance, as no user adjustment is required. The laser intensity, however, is user adjustable... [See More]
- CDRH Classification: Class II; Class IIIb; Class IIIR
- Laser Output: Continuous
- Laser Type: Laser Diode Modules
- Laser Wavelength: Red
from Diode Laser Concepts, Inc.
635nm, industrial module, 10 ° line [See More]
- CDRH Classification: Class II
- Laser Wavelength: Red
- Laser Type: Laser Diodes
- Wavelength Range: 635
from ProPhotonix, Ltd.
An economical range of compact, 8mm diameter, laser diode modules for integration into systems and handheld instrumentation where space is at a premium. Typical applications are targeting, industrial alignment such as pre-press plate alignment, laser alignment for label and wrapper cutting machinery... [See More]
- CDRH Classification: Class II; Class IIIb; Class IIIR
- Laser Output: Continuous
- Laser Type: Laser Diodes (optional feature)
- Laser Wavelength: Red
from ProPhotonix, Ltd.
The DPSS green laser module is a compact, self-contained laser module designed for use in industrial alignment, medical and scientific applications where a highly visible beam is required. It produces a very visible circular output beam of <2.0mm diameter and output powers of 0.9mW and 4mW with a... [See More]
- CDRH Classification: Class II; Class IIIb; Class IIIR
- Laser Output: Continuous
- Laser Type: Laser Diodes (optional feature); Laser Diode Modules
- Laser Wavelength: Green
from ProPhotonix, Ltd.
Industrial laser diode modules are designed to be a complete OEM laser solution for heavy duty industrial manufacturing processes such as micro-machining, marking, cutting, drilling, welding, forming, soldering and many other industrial laser uses where superior quality, durability and performance... [See More]
- CDRH Classification: Class II; Class IIIb; Class IIIR
- Laser Output: Continuous
- Laser Type: Laser Diodes (optional feature); Laser Diode Modules
- Laser Wavelength: Red; Infrared
from ProPhotonix, Ltd.
InViso ™ is an innovative range of diode based laser modules designed to meet the demanding requirements of high thermal performance machine vision applications at wavelengths ranging from the UV to the infrared and power levels up to 100mW. Focused on customer needs rather than... [See More]
- CDRH Classification: Class II; Class IIIb; Class IIIR
- Laser Output: Continuous
- Laser Type: Laser Diodes (optional feature); Laser Diode Modules
- Laser Wavelength: Red
from ProPhotonix, Ltd.
The Photon laser module is a self-contained laser diode module designed as a complete OEM laser solution for industrial, medical and biomedical applications. Lasing wavelengths range from 635nm, 705nm to 850nm, with an elliptical output beam and optical output powers from 0.9mW to 85mW. The laser... [See More]
- CDRH Classification: Class II; Class IIIb; Class IIIR
- Laser Output: Continuous
- Laser Type: Laser Diodes (optional feature); Laser Diode Modules
- Laser Wavelength: Red; Infrared
from ProPhotonix, Ltd.
An economically priced range of circular beam, threadmount laser diode modules for OEM use in applications where precision and reliability are important, such as industrial alignment and positioning. Wavelengths range from 635nm to 670nm. The laser module consists of an aluminum housing, laser... [See More]
- CDRH Classification: Class II; Class IIIb
- Laser Output: Continuous
- Laser Type: Laser Diodes (optional feature); Laser Diode Modules
- Laser Wavelength: Red