Laser Driver Circuit and Laser Display

A laser display which scans a laser beam across a screen so as to display an image on the screen, the laser display comprising:

• a laser diode for emitting the laser beam;
• a laser driver circuit which supplies the laser diode with a current so as to drive the laser diode;
• and
• a scanning means for scanning the laser beam emitted by the laser diode across the screen,
• wherein the laser display displays the image on the screen not only by controlling scanning of the scanning means to control a laser beam irradiated position on the screen, but also by controlling driving of the laser diode using the laser driver circuit so as to control the radiance of the laser beam to be irradiated on the screen,
• wherein the laser driver circuit comprises a current supply circuit for supplying the laser diode with the current,
• wherein the current supply circuit comprises:
• a voltage-to-current converter circuit for converting an input voltage to the current so as to generate the current;
• a current output line which is connected to the voltage-to-current converter circuit, and which outputs the current generated by the voltage-to-current converter circuit;
• a current supply line which is connected to the laser diode, and which supplies the laser diode with the current generated by the voltage-to-current converter circuit;
• a ground line connected to the ground;
• and
• a current path switch for selectively connecting either the current supply line or the ground line to the current output line,
• wherein the current which is output from the voltage-to-current converter circuit, and which is running through the current output line, the current path switch and the current supply line is supplied to the laser diode so as to drive the laser diode, and
• wherein the laser driver circuit further comprises a current output prevention circuit for preventing the voltage-to-current converter circuit from generating the current and preventing the current from being output from the current output line, when the current output line and the ground line are connected by the current path switch.