by jplee » Wed May 02, 2018 2:51 pm
Hi, I think it is this:
Operational modes of a ferroelectric LCoS modulator
https://www.uv.es/gpoei/articulos/(2009 ... atings.pdf
Its quite technical maths though, but basically by modifying the polarization, a cheaper (binary) display projector can function for phase modulation instead of amp modulation. Note however that different techniques are used in different projectors, so taking apart a random display projector will not work if it is not LCOS (liquid crystal on silicon). There are types that use micro mirrors (DMD) and those with color filter built in to the SLM and these might not operate for phase modulation even when modified. A helpful indicator is if the projector intrenally has 3 (r,g,b) light sources, instead of 1 white bulb, but DMD can also have 3 sources...
For papers, I think important keywords are FLCOS (F = ferroelectric) and binary. Cheaper modded display projectors only have 2 phase levels (normally 0, pi) unlike research SLMs that normally have 256 phase levels.
This is a clearer example of a binary LCOS for phase modulation, but I'm not sure if it is from a display projector
"Wavelength-compensated color Fourier diffractive optical elements using a ferroelectric liquid crystal on silicon display and a color-filter wheel"
https://www.osapublishing.org/ao/abstra ... o-48-5-911 (not open access)
I recall research SLMs are around 10,000 to 20,000 eur, so normally only universities or companies have them.
Hi, I think it is this:
Operational modes of a ferroelectric LCoS modulator
[url]https://www.uv.es/gpoei/articulos/(2009)%20AO%20Operational%20modes%20of%20a%20ferroelectric%20LCoS%20modulator%20for%20displaying%20binary%20polarization,%20amplitude,%20and%20phase%20diffraction%20gratings.pdf[/url]
Its quite technical maths though, but basically by modifying the polarization, a cheaper (binary) display projector can function for phase modulation instead of amp modulation. Note however that different techniques are used in different projectors, so taking apart a random display projector will not work if it is not LCOS (liquid crystal on silicon). There are types that use micro mirrors (DMD) and those with color filter built in to the SLM and these might not operate for phase modulation even when modified. A helpful indicator is if the projector intrenally has 3 (r,g,b) light sources, instead of 1 white bulb, but DMD can also have 3 sources...
For papers, I think important keywords are FLCOS (F = ferroelectric) and binary. Cheaper modded display projectors only have 2 phase levels (normally 0, pi) unlike research SLMs that normally have 256 phase levels.
This is a clearer example of a binary LCOS for phase modulation, but I'm not sure if it is from a display projector
"Wavelength-compensated color Fourier diffractive optical elements using a ferroelectric liquid crystal on silicon display and a color-filter wheel"
[url]https://www.osapublishing.org/ao/abstract.cfm?uri=ao-48-5-911[/url] (not open access)
I recall research SLMs are around 10,000 to 20,000 eur, so normally only universities or companies have them.