Andy Resnick said:This is a fairly standard problem: place the prism surfaces confocal to the focal point of an f-theta lens:
http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productid=2961
Then it's all geometry. In fact, there are commercial solutions: look around and copy their design.
moapz said:thanks andy.
can you introduce reference for optic or laser beam?
Andy Resnick said:It's just geometry- for example, you say the scanning mirror generates a 1 cm line, how far from the mirror is the 1 cm line? Clearly, as you get farther and farther away, the size of the line (rectangle) will increase.
What I am asking about is the *divergence* of the scanned beam. Instead of linear sizes, think about the angles- through what angle is the beam scanned?
A laser beam expander is an optical device that increases the diameter of a laser beam while maintaining its collimation (meaning the beam remains parallel). It works by using a combination of lenses to magnify the beam and reduce its divergence, resulting in a larger and more collimated beam.
A laser beam expander is typically used when a laser beam needs to be expanded to cover a larger area or when a more collimated beam is required for a specific application. This is often necessary in laser machining, laser cutting, and laser drilling processes.
When selecting a laser beam expander, factors such as the required beam diameter, beam divergence, and wavelength of the laser should be taken into account. It is also important to consider the quality of the lenses and coatings used in the expander, as well as any necessary adjustments or alignment procedures.
The magnification of a laser beam expander can be calculated by dividing the output beam diameter by the input beam diameter. For example, if the input beam has a diameter of 2 mm and the output beam has a diameter of 10 mm, the magnification would be 10/2 = 5x.
Yes, it is important to follow standard laser safety procedures when using a laser beam expander. This includes wearing appropriate laser safety glasses or goggles and ensuring that the beam is not directed towards any person or reflective surfaces. It is also important to regularly inspect and maintain the expander to ensure it is functioning properly and safely.