We present the design of a large-area (50 mm x 50 mm) PVDF pyroelectric sensor array for industrial CO2 (l=10.6 mm) laser beam positioning. The array dimensions were chosen to match the area typically monitored by technical operators in the alignment procedure of external optics (beam steering moving arm system, for example) used to redirect the laser beam from the laser output window to a remote working station. The instrument is provided with a tilted, high reflection, ZnSe plate which partially transmits the laser beam onto the sensor array. From positioning simulations with a Gaussian laser intensity profile with a s = 3.2 mm standard deviation (equivalent spot size 3s @ 20 mm), the positional accuracy along the two orthogonal array dimensions was found to be better than 0.02 mm for an 8x8 array and one order of magnitude higher for a 16x16 array. The centroid position was evaluated by the integrating the pyroelectric current in times comparable to (lower than) the time duration of CO2 industrial laser pulses typically lasting 100-200 ms in the alignment procedures.
A Large-Area PVDF Pyroelectric Sensor for CO2 Laser Beam Alignment
Marina Mazzoni;
2007
Abstract
We present the design of a large-area (50 mm x 50 mm) PVDF pyroelectric sensor array for industrial CO2 (l=10.6 mm) laser beam positioning. The array dimensions were chosen to match the area typically monitored by technical operators in the alignment procedure of external optics (beam steering moving arm system, for example) used to redirect the laser beam from the laser output window to a remote working station. The instrument is provided with a tilted, high reflection, ZnSe plate which partially transmits the laser beam onto the sensor array. From positioning simulations with a Gaussian laser intensity profile with a s = 3.2 mm standard deviation (equivalent spot size 3s @ 20 mm), the positional accuracy along the two orthogonal array dimensions was found to be better than 0.02 mm for an 8x8 array and one order of magnitude higher for a 16x16 array. The centroid position was evaluated by the integrating the pyroelectric current in times comparable to (lower than) the time duration of CO2 industrial laser pulses typically lasting 100-200 ms in the alignment procedures.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
