Seimans LGR7631A Laser Pointer

by JRV31 in Circuits > Lasers

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Seimans LGR7631A Laser Pointer

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A while back a friend gave me this laser he found in a silicon valley surplus store. It sat around for a while before I decided to try to get it working. It is kind of beat up and looks like it had been sitting at the bottom of someone's junk box for a long time. The manufacturing date on the sticker on the tube says March 1987. After soldering a few broken connections I had it working with the pieces spread out on my desktop.

The driver board is mounted to the plywood with 4 #6x1 inch wood screws and 4 1/2 inch nylon spacers.

The transformer and the laser tube are each mounted with 2 #6x1/2 inch wood screws.

The laser tube is a Siemens LGR 7631A 1.5-2.5mW laser. (Not powerful enough to pop a balloon and not a lot more powerful than a little battery powered laser pointer.)

Do not point lasers at people, and I don't recommend them for cat toys, you might accidentally hit them in the eyes.

The laser can be found online, search duckduckgo.com for Siemens LGR 7631A.

The Laser Tube

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Shown lighted and unlighted.

Connector

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The wires from the driver board to the tube are very flexible fine stranded wire with thick insulation.

This is the polarized connector that connects the driver board to the laser tube.

Transformer?

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I am guessing a high voltage, high frequency transformer.

Connected with bayonet connectors, not polarized, I was careful to remember the polarity.

Driver Board

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The driver board and a closeup of the daughter board, which appears to be a filter and regulator.

T-shirt

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Just in case you are wondering, this is the image on the t-shirt that is partially covered in the intro picture.