I bother you for help.
I am trying to write a LPG into a photosensitive fiber type Nufern GF1 by point to point technique (i.e. I am using a shutter to block the beam and making a pattern with period 400um). I have used a power of50mW and the beam is focused into a spot of 200um, the exposure time is 3min per cell, 60 cells . The result is: nothing!
Does anybody have an idea about what I do wrong?
I have some dubts already, but I am not sure whether they are correct or not:1) the photosensitivity is still too low and I will never get anything with this laser (I cannot send in more power) 2) I do not make beam filtering to avoid the waste of power. Does this limit the focusing due to abberations?
Thanks in advance to anybody who can give me some hints!