Encyclopedia … combined with a great Buyer's Guide!

VLib
Virtual
Library
Sponsoring this encyclopedia:     and others

Direct Diode Lasers

Acronym: DDL = direct diode laser

Definition: diode lasers which are directly used e.g. for material processing

Category: lasers

How to cite the article; suggest additional literature

Author:

Direct diode lasers are laser devices where the output of laser diodes is directly used for an application – frequently in laser material processing, e.g. in the form of laser cutting or laser welding. This is in contrast to using diode-pumped lasers, where the diode laser radiation is used for pumping another laser, typically a solid-state laser, the output of which is then sent to the application. That additional laser usually acts as a brightness converter: although some of the optical power is lost, the beam quality of its output is so much higher than that of the diode laser(s) that the brightness (more precisely: the radiance) is still higher. This allows for increased optical intensities on workpieces, for example.

The direct use of diode lasers is attractive for different reasons:

Advantages and Limitations

However, the beam quality of high-power laser diodes has for many years been clearly too low for direct application e.g. for laser welding. The rapid technical progress in this area has in recent years increased their beam quality and radiance to such high levels that many direct diode applications have become possible. Direct diode lasers are therefore now even used for metal cutting and welding, particularly for conduction welding of relatively thin metal sheets. Laser soldering and brazing, laser cladding and some laser surface treatments also belong to their applications.

Technical Basis for Performance Improvements of Direct Diode Lasers

The improved radiance of high-power laser diodes has different origins. One factor is the continuous increase of radiance of diode bars and diode stacks through improvements of their design. For example, there are tapered laser diodes and tapered amplifiers with much increased beam quality. Another factor are improved methods and components for beam combination of the radiation of many laser diodes.

Free Space or Fiber Coupling

In the same way as solid-state lasers, direct diode laser products can either emit a free-space laser beam or can be fiber-coupled. Beam delivery through an optical fiber is beneficial for many applications, and becomes feasible if the beam quality of the source is sufficiently high.

Suppliers

The RP Photonics Buyer's Guide contains 14 suppliers for direct diode lasers.

Questions and Comments from Users

Here you can submit questions and comments. As far as they get accepted by the author, they will appear above this paragraph together with the author’s answer. The author will decide on acceptance based on certain criteria. Essentially, the issue must be of sufficiently broad interest.

Please do not enter personal data here; we would otherwise delete it soon. (See also our privacy declaration.) If you wish to receive personal feedback or consultancy from the author, please contact him e.g. via e-mail.

Your question or comment:

Spam check:

  (Please enter the sum of thirteen and three in the form of digits!)

By submitting the information, you give your consent to the potential publication of your inputs on our website according to our rules. (If you later retract your consent, we will delete those inputs.) As your inputs are first reviewed by the author, they may be published with some delay.

See also: diode lasers, diode-pumped lasers, solid-state lasers, brightness converters, beam combining, laser applications
and other articles in the category lasers

preview

If you like this page, please share the link with your friends and colleagues, e.g. via social media:

These sharing buttons are implemented in a privacy-friendly way!