What is this?

[oversky]

Today I received my GGW-H20L, and tried to seperate the diode from the the read/write module. I saw a device that I can't recognize its function.

This device sits just in front of the laser diode.
Is it some kind of photo detector for auto power control?

 

[magonegro]

Seems like a PCAOM, ( PolyChromatic Acoustic-Optical Modulator ).

 

[ped]

Seems like a PCAOM, ( PolyChromatic Acoustic-Optical Modulator ).

Christ you'd win every time at hangman with that?!? :crackup:


I thought it was an attenuator :undecided:

 

[oversky]

I don't think it is an attenuator. First, an attenuator doesn't need wires. Second, there is no reason to add an attenuator just in front of the laser. We can reduce the laser power by decreasing the current.

 

[HIMNL9]

Looks like an LCD panel, without polarization filters.

As probably you know, LCD panels works rotating the polarized light that pass through them from 0 to 90 degrees, proportionally to the driving voltage, so it can be a polarization rotator.

Not a corrector like the ones in the PHR and similar sleds, anyway, this one have just the 2 wires for the entire panel, no sectors and no interface.

 

[ped]

I don't think it is an attenuator. First, an attenuator doesn't need wires. Second, there is no reason to add an attenuator just in front of the laser. We can reduce the laser power by decreasing the current.

Thats why i decided it wasnt an attenuator.

 

[Cyparagon]

PCAOMs are much larger and require RF. Why would a monochromatic light source require a poly-chromatic modulator anyway?

Did you just feel like saying a big word?

 

[magonegro]

PCAOMs are much larger and require RF. Why would a monochromatic light source require a poly-chromatic modulator anyway?

Did you just feel like saying a big word?

Absolutelly not. Most of the times I am wrong. :crackup:

 

[HIMNL9]

Well, you can probably build an AOM from this thing and a polarizer filter ..... place them one rear the other, rotated in the way that you can see through them the better possible (less possible loss), then driving the panel, you can modulate the beam intensity ..... cheapy hobby-made AOM

 

[qumefox]

Technically that would just be a optical modulator. If your not driving a crystal with RF, you lose the acoustic part.