The laser beam of laser pointer large in the energy density

The laser beam of laser pointer large in the energy density
If the bias point close to the curve at the bottom of the wave part, will cause severe nonlinear distortion. Broadband modulation to the laser modulation circuit to maintain the input current waveform is not only important to circuit design, circuit technology is equally important, because the stray inductance and stray capacitance to give the high frequency component adversely affect, to some extent will also affect the optical transmitter nonlinear distortion indicators. Laser protection circuit. The semiconductor laser is an expensive device, and protected from damage should be noted that in practical circuit applications in the optical transmitter is very important to the protection of the laser, but it still belongs to the auxiliary circuit of the optical transmitter. Also, the customer needs to consider the location situation or condition of the occasion of laser pointer .
The protective measures of the laser source requirements should be: First, reliable and is simple, does not affect the light work properly. Protect the laser is not damaged points to prevent acute damage and prevent long-term chronic damage. LD is short-term protection. The short-term acute damage to the main factors of laser overcurrent and instantaneous impact, and thus the short-term protection measures laser main boot delay protection and current limit protection. Boot delay protection is to prevent the moment of the optical transmitter power in the boot, due to damage to the circuit caused by the overshoot may be caused by the laser; boot delay Protection Act laser DC bias current delay access law and the DC bias current and modulation current of the laser delay to protect the French. The color of the laser beam light of laser pointer should also be stated clearly.
From the protective effect, the latter is simple and practical point of view, the former than the latter. Laser DC bias current-limiting protection law, there are two: First, the resistor current limiting protection law, diversion protection law. Measures and technologies used by various manufacturers are not consistent, but the effectiveness of play should be consistent, that is, must ensure that the optical transmitter power, must wait for the laser driver circuit in the DC bias and modulation current conditions into a stable state, the temperature control circuit into a stable state after a slow increase in the laser DC bias current and modulation current into the normal working state.