Product and Technology Release of Red Laser Diode for Sensing and Bio-Medical Applications ― Achieving the world’s highest CW optical output power of 200mW at 660nm ―

Ushio Opto Semiconductors, Inc. (Head Office: Tokyo, President and CEO: Hiroaki Banno), a wholly-owned subsidiary of Ushio Inc., will release a new 660nm red laser diode for sensing and bio-medical applications in February 2020. This series (HL65221DG) achieves the world’s highest single mode CW optical output power*¹ of 200mW*².

The product will be exhibited at the company’s booth at SPIE Photonics West 2020, held at the Moscone Center in San Francisco, CA, U.S. during February 4th through 6th. A presentation will also be given at the OPTO Conferences on February 3rd.

■Red LD applications for various wavelength ranges Red LDs composed of AlGaInP-based materials are widely used in the wavelength range of 630nm to 690nm because of their high output, high efficiency, excellent beam quality, and high reliability. Additionally, they have the advantage of lowering the power consumption of the equipment using the LDs, allowing them to be used as light sources for various applications.

In particular, LDs in the 630nm to 640nm wavelength range, which have relatively high visibility, have been put to practical use for display applications such as digital cinema projectors and show lasers. Future requirements are trending toward higher output and higher efficiency in order to achieve higher brightness and better color reproducibility for the projectors.

The use of LDs in the 660nm band, which are widely used as light sources for writing data on optical disks, is expected to expand in sensing and biomedical applications in the future.

Due to the excellent temperature performance and visibility of red LDs in the 660nm band, practical use has already begun within the field of industrial sensing applications, including photoelectric sensors, distance meters, and total stations. They are also being used in biomedical applications such as flow cytometry, photodynamic therapy, and DNA sequencing, as well as laser microscopes and Raman spectroscopy.

■Challenges and solutions for LD for sensing and biomedical application Single-mode LDs for sensing and biomedical applications have recently required long-distance measurement, high resolution, high throughput, etc. in order to further improve the equipment’s performance. For biomedical applications in particular, higher output and good beam quality are required to quickly realize photochemical reactions in the corresponding wavelength band with high efficiency.

The 660nm band single mode LDs can achieve its advantageous temperature characteristics through an increase in the doping concentration*³ of the AlGaInP-based material. However, a higher doping concentration reduces the reliability. As such, it was challenging to achieve both good temperature characteristics and high reliability, and the CW optical output power was found to be limited at ~100mW.

Ushio Opto Semiconductors solved this problem by combining their crystal growth technology and knowledge of output power improvement with the commercialization of this single mode LD. HL65221DG has achieved the world's highest CW optical output power of 200mW at 660nm, as well as pulsed optical output power*⁴ of 400mW, as it is also capable of high-power operation with the short pulse width required for various applications. This will contribute to the increase of red LD-equipped sensors and biomedical devices.

• 1 Continuous oscillation of given optical output power
• 2 An internal investigation as of January 2020
• 3 Highly charged particle density in semiconductor
• 4 Oscillation of optical output power at given repeated intervals

■Features 1. Achieved the world's highest CW optical output power of 200mW with 660nm wavelength single mode LD.
2. Supports pulsed operation and achieves pulsed optical output power of 400mW.
3. Achieved wall plug efficiency of 32% and stable operation at single transverse mode.
4. High temperature operation at 75°C despite its small size of 5.6mm TO-CAN.
5. Commercialized three types of internal circuit to meet various to customer applications.（Refer product picture and internal circuit）
6. Built-in monitor photodiode contributes to simplification of circuit configuration.

■Product specification(Operating temperature Tc=25℃)

Product image, Internal Circuit

For further information, please contact: Ushio Inc.
TEL. ＋81 75-682-2338　FAX. ＋81 75-682-2267
Please use the online inquiry formon our website.