Laser-Pen

Team Members

Groß Herbert, Pichler Markus, Schönbauer Martin

Tutors

DI Gerhard Jüngling MBA, DI Roland Glas

conceptual formulation

Bild 1

The laser-pen is basically designed for the so-called surface-radiation, which is applied at a distance of a few millimeters from the skin.
To make the project more interesting, a sliding switch, which is used to choose the intensitiy radiation (2 Joule and 4 Joule), has been installed.

To secure the Laser-Pen against unauthorized use, a key-operated switch is integrated.
Additionally, a pushbutton to start the radiation is attached to the laser-pen. If this button is no longer pressed, the radiation will stop immediately.

In addition, a light emitting diode (LED) is used to signify the readiness for use. In case of the voltage being too low, the light emitting diode will begin to blink. Furthermore a buzzer signals the readiness and the end of the treatment.
The operator is free to decide when the procedure should be stopped, all he has got to do is let go the switch.

Furthermore it was part of the definition of the job to deal with the guidelines regarding to the contact with lasers. As a result of this two high-quality protection goggles have been selected.

details on execution

Bild 2

One aim of this project was that the laser-pen is compareable to products which are already existing on the market.
Regarding to the development of the case attention was paid to design the laser-pen as small as possible. To enable a uncomlicated application the case should be designed very simple and clear arranged.
Due to these requirements the board has to be sized 80x15 mm.

It was very important to ous, that we can ensure, thatt the optical output power is kept stable. For this reason a regulation circuit is available. This circuit uses the monitoring diode,which is integrated in the laser diode, to control the laser-diode-current. Using a potentiometer enables adjusting the operating point of the regulation circuit. This enables the use of several laser diodes with this hardware.
The entire circuit is controlled by a micro controller. To ensure a stable output power while the voltage-supply is dropping, the laser-pen is able to deactivate the laser diode and to display the need that the accumulator batteries need to be recharged with the help of an enclosed uni-recharger.
HTL Wien 3 Rennweg, Mai 2007