Looking for MANUFACTURER of any product (liquid, glass, crystal,
plastic etc) of which the refractive index can be adjusted acording to
the amount of electrical current applied. The product must be able to
have light pass through it.

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Clarification of Question by mrwiseone-ga on 06 Feb 2003 18:25 PST

please contact me if this is not a reasonable price!

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Request for Question Clarification by hlabadie-ga on 10 Feb 2003 09:21 PST

Have you assessed the properties of LCS products?

hlabadie-ga

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Clarification of Question by mrwiseone-ga on 10 Feb 2003 13:42 PST

No. What are LCS products? The product would need to be able to be
manufactured into a prism.

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Request for Question Clarification by hlabadie-ga on 10 Feb 2003 21:45 PST

It's the technology typically used in the lenses of goggles intended
for stereoscopic computer displays. It can switch from transparent to
opaque virtually instantaneously. It is also used on windows. Do you
want this information as an answer?

hlabadie-ga

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Clarification of Question by mrwiseone-ga on 11 Feb 2003 15:47 PST

To clarify it a little. What I'm trying to do is; take a single narrow
beam of light, shine it onto a prism, which then splits and bends the
light. On a normal prism a particular wave length (eg 600nm)will
always come of at the same angle to the face of the prism (eg angle
X). I want to be able to shine the light through the prism and have
600nm wave length come out of the prism at angle X, then change the
optical density / refractive index (some how) so that I can have wave
length 700nm or 800nm etc come out at angle X (the same angle).

I have heard that there are products that can change their optical
density witht the application of electricity and or application of
varying wavelengths of laser light.

I greatly apreciate your efforts in this. I havn't been able to find a
thing! And I am quite handy on the Google search!

Silly things us non-scientific people want to be able to do!

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Request for Question Clarification by hlabadie-ga on 11 Feb 2003 20:57 PST

Here is what the spec sheet from one manufacturer says:

"A shutter is made from an FLC cell, formed when an FLC layer is
sandwiched between two glass substrates, each with a transparent
electrode on their facing surfaces. Voltage applied between these
electrodes switches the orientation of the FLC molecules’ optic axis
into one of two states, changing the polarization of the outgoing
light. FLC cells become shutters when placed between linear crossed
polarizers or alternatively by the use of a polarized light source and
one linear polarizer."

"Operating wavelength range 2 400-700 nm (center l = 510 ± 25 nm)
Angular acceptance 20° (max), 0.34 N.A. or f/1.4"

"Custom shutters can be manufactured with center wavelengths from 400
to 1500 nm."

It seems that you might want something like a diffraction grating and
polarizer, however.

hlabadie-ga

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Clarification of Question by mrwiseone-ga on 12 Feb 2003 16:34 PST

That wasn't exactly what I was looking for. However, could the screen
be made opaque except for a narrow strip? If so could this transparent
strip be as narrow as 0.1 millimeters or less? Whould this be able to
split the light into it's component wave lengths? And could the
transparent strip be moved left or right acording to which cells were
turned on or off? If so it would be perfect.

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Request for Question Clarification by hlabadie-ga on 12 Feb 2003 21:03 PST

Hypothetically, if the LCS had the same matrix address circuitry and
drivers as a regular LCD, then the resolution could be as fine as a
single cell of the matrix. I don't know if that is possible, however.
You would have to consult the manufacturers directly.

A diffraction grating, on the other hand, performs the same task as a
prism, and a system of mirrors and lenses could manipulate the
portions of the spectrum that you selected in any way that you wished.

This is getting far from the original question, "any product of which
the refractive index can be adjusted." The LCS does that, but the
subsequent clarifications make it less clear what the question has now
become. I'm really not sure what would constitute a suitable answer at
this point. There might not be one that meets all the additional
conditions.

hlabadie-ga

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Clarification of Question by mrwiseone-ga on 12 Feb 2003 22:03 PST

Ok supply the information, I'll chase them from here. Thank you.

LIQUID CRYSTAL SHUTTERS (LCS)

The answer to original question,

"Looking for MANUFACTURER of any product (liquid, glass, crystal,
plastic etc) of which the refractive index can be adjusted acording to
the amount of electrical current applied. The product must be able to
have light pass through it."

is Liquid Crystal Shutters. LCS are similar to the ordinary LCD used
in computer displays, except that they alter their polarization axis
to transmit or block light when used with a polarized light source or
polarized filter. This is a mature technology and is relatively cheap.
It is used in photography to replace mechanical shutters, eliminating
all shutter vibration, in printer engines instead of laser scanning or
LED sources, and in computer generated stereoscopic displays. The
technology is also used in high-end windows for privacy and solar
shading. It is doubtful that it will be useful in your intended
application, however, although it does show up in spectrometers.


Purnendu K. Dasgupta
CURRICULUM VITA November, 2002
http://www.depts.ttu.edu/chemistry/faculty/dasgupta/PurnenduKwebCV.htm

A Liquid-Crystal Shutter-Array Spectrometer. H. S. Bellamy and P. K.
Dasgupta and J.  L. Lopez, and Ellis L. Loree. Spectroscopy 10 (6),
50-54 (1995).

CHARACTERIZATION OF A COFLOWING METHANE/AIR NON-PREMIXED FLAME WITH
COMPUTER MODELING, RAYLEIGH-RAMAN IMAGING, AND ON-LINE MASS
SPECTROMETRY
http://guilford.eng.yale.edu/pdfs/coflow_flame.pdf


One very fast switching version is the ferro-electric liquid crystal
shutter (FLCS or FLC). There are manufacturers who can produce custom
LCS.

LCS MANUFACTURERS

DISPLAYTECH
http://www.displaytech.com/downloads/Shutters.pdf

"A shutter is made from an FLC cell, formed when an FLC layer is
sandwiched between two glass substrates, each with a transparent
electrode on their facing surfaces. Voltage applied between these
electrodes switches the orientation of the FLC molecules’ optic axis
into one of two states, changing the polarization of the outgoing
light. FLC cells become shutters when placed between linear crossed
polarizers or alternatively by the use of a polarized light source and
one linear polarizer."

"Operating wavelength range 2 400-700 nm (center l = 510 ± 25 nm)
Angular acceptance 20° (max), 0.34 N.A. or f/1.4"

"Custom shutters can be manufactured with center wavelengths from 400
to 1500 nm."


"For price and availability, please contact the Photonics sales
department at Displaytech. Prices are subject to change without
notice.
Displaytech shutters are covered by a limited, one-year warranty.
The FLC material will be damaged by exposure to UV radiation. It is
the customer’s responsibility to check with the manufacturer of a
light source for UV components. If the shutter will be exposed to UV
radiation or if there is any doubt, the shutter must be used with a UV
blocking filter for the warranty to be valid."

CRLOPTO
http://www.crlopto.com/products/datasheets/files/LCS2-datasheet.pdf
http://www.crlopto.com/products/datasheets/files/Custom-shutters.pdf




OPTICAL PHASED ARRAYS

The answer to your clarified question is Liquid Crystal Optical Phased
Arrays on Silicon (LCOPAS).

LCOPAS are miniaturized versions of OPA that are typically used in a
large variety of optical applications, such as laser steering,
spectroscopy, network switching, etc. This is an immature technology
and has only recently emerged from the lab into production. To my
knowledge, there is one manufacturer, Raytheon. It is highly doubtful
that this is a commercially available product at this time, however.

LCOPAS

School of Optics/CREOL School of Optics/CREOL HIGHLIGHTS
http://www.creol.ucf.edu/About/Highlights/HLspr02.pdf

"High birefringence liquid crystals"

"Raytheon’s optical phased arrays"

"Similar to TFT-LCD, the phase change of each pixel in the applied
voltage. Therefore, we can synthesize the phase profile digitally. OPA
is a versatile device. It can be used to steer a laser beam for free
space communication, network switching for fiber-optic communication,
beam fanning, and electronic lens and prisms."


ALSH 1 (IEEE Lenses and Electro-Optics Society (LEOS) Conference
agenda) Wednesday, 13 November 2002
http://www.ieee.org/organizations/society/leos/LEOSCONF/LEOS2002/le02wed.pdf

14.00 - 15.30
Session WT: LIQUID CRYSTALS FOR AGILE BEAMS
Session Chair: M.J. Mughal, Nuonics Inc., Orlando, FL, USA
WT1 14.00 - 14.30 (Invited)
Liquid Crystal Optical Phased Arrays: Practical Issues and
Applications, S. Harris, US Air Force Research Lab, WPAFB, OH, USA
Liquid Crystal Optical Phased Arrays (LCOPAs) are exciting, new
optical devices that promise to revolutionize a wide variety of
optical systems. However, their relative immaturity compared to other
optical components means that there is not an extensive experience
base from which to draw when an engineer is considering incorporating
LCOPA technology into a new optical design.

WT2 14.30 - 15.00 (Invited)
High Birefringence Liquid Crystals for Laser Beam Steering, S.-T. Wu,
S. Gauza and H. Wang, University of Central Florida, Orlando, FL, USA
High birefringence (~0.5) liquid crystal compounds and mixtures are
developed for laser beam steering using an optical phased arrays
device. At 70C, the new UCF mixture exhibits a figure of merit 10X
higher than that of E7.

WT3 15.00 - 15.30 (Invited)
Liquid Crystal Adaptive Optics, G. D. Love and A. F. Naumov,
University of Durham, UK
This paper describes the recent progress in using liquid crystals in
adaptive optics. In particular we describe work on liquid crystal
phase modulators as lenses and wavefront controllers.

Also of interest, because micromirror OPA are also in limited use:

Session WBB: MICROMIRRORS AND OPTICAL MEMS
Session Chair: Nabeel A. Riza, University of Central Florida, Orlando,
FL, USA

WBB1 16.00 - 16.30 (Invited)
Agile Beams and Micromachined Membrane Deformable Mirrors, G. Vdovin
and P. M. Sarro, Delft University of Technology, The Netherlands
Micromachined membrane deformable mirrors (MMDM) for agile control of
light are described. The applications include control of the intensity
and phase of light, fiber switching, SLM, laser intracavity adaptive
optics and femtosecond pulse compression.

WBB2 16.30 - 16.45
3-Dimensional Wide Angle Optical Scanning using Code-Multiplexed
Optical Scanner, M. A. Arain and N. A. Riza, University of Central
Florida, Orlando, FL, USA
We report a 3-dimensional optical scanner based on 2-dimensional phase
coded holograms stored in a photorefractive crystal. The optical
scanner is capable of delivering wide scan angles (e.g. > 50 degrees)
with large aperture sizes.

WBB3 16.45 - 17.15 (Invited)
Optical MEMs based on Silicon-on-Insulator (SOI) for Monolithic
Optical Microoptics, W. Noell, W. Sun, N. de Rooij, H. P. Herzig, O.
Manzardo, and R. Dändliker, University of Neuchâtel, Switzerland
Microelectromechanical systems (MEMS) combined with optical components
add optical functionality to devices and led to the terms Optical MEMS
or MOEMS. The underlying technology of the presented devices is the
silicon-on-insulator (SOI) based batch fabrication, which delivers
small, reliable and lasting monolithic bulk silicon structures for
commercial devices with the advantage of being very insensitive to
temperature changes. The particular strength of the technology are
monolithic horizontal and vertical micromirrors for a variety of
applications.

WBB4 17.15 - 17.45 (Invited)

MEMS WDM Routers Using Analog Micromirror Arrays, M. C. Wu, J. C Tsai
and S. Huang, University of California, Los Angeles, CA and D. Hah,
ETRI, Seoul, Korea
We report on the recent progresses in our MEMS
wavelength-division-multiplexed (WDM) Routers that employ a linear
array of analog micromirrors to perform wavelength switching among
multiple fibers.

LEOS NEWSLETTER
http://media.i-leos.org/pdf/newsletters/leos1297.pdf

The MACH - a novel, electrically controllable hologram
"Computer generated holograms (CGH) behave essentially as
conventional, interferometrically recorded holograms, but they are
designed by computer and fabricated using techniques more associated
with the semiconductor industry. They allow optical wavefronts to be
generated without the need for any holographic recording step. As a
consequence of this, they permit light distributions to be formed that
would otherwise be impossible to generate, e.g. generation of 3D
images of non-existent objects. Over the last few years, advances in
CGH, microstructure fabrication and liquid crystal displays have
resulted in new classes of active diffractive devices. These allow CGH
and other diffractive devices to be 'switched' under electrical
control."
[...]
"Recently the liquid crystal/dielectric substrate idea has been
extended to produce a new class of devices which are capable of
producing independent, multiple wavefronts when specific voltages are
applied across the device."


LCOPAS MANUFACTURER

RAYTHEON

Air Force Office of Scientific Research (AFOSR)
FY 97 Technology Transitions/Transfers
http://www.afosr.af.mil/pdfs/afrtt98.pdf

2303C Polymer Chemistry Lee Dr S.T. Wu, Hughes
Research Labs, (310) 317- 5901
Raytheon Company, Terry Dorschner, (617) 860-3071
New liquid crystal mixtures Laser beam steering using optical phased
arrays developed at Raytheon Company

Raytheon 2001 Annual Meeting
http://www.raytheon.com/feature/anmeet/index.html

"Electronic Systems' Terry Dorschner, from Lexington Labs, was
recognized for leadership in optical phased array technology."


DIFFRACTION GRATINGS

A much simpler and cheaper and more readily available solution for
your problem can be constructed from diffraction grating, beam
splitters, and polarizers, using mirrors, lenses, and filters.

University of Illinois

Experiment D-7
SPECTROSCOPY USING A DIFFRACTION GRATING MONOCHROMATOR
http://wug.physics.uiuc.edu/courses/phys371/371exp/D7/D7.pdf

"The equipment used in this lab – a computer-controlled diffraction
grating monochromator and PMT used in single-photon counting mode
enables one to carry out spectroscopic studies on essentially an
arbitrary (emission) source of light, such as:
1. Raman Scattering/Raman Spectroscopy.
2. Emission lines from Sodium and Mercury discharge lamps.
3. Fluorescence Studies.
4. Absorption Studies."

SMU Physics Department
Diffraction (Experiment with formulae)
http://www.physics.smu.edu/~ryszard/1314sp98/1314_diffrac_.PDF


BASIC GRATINGS

Rainbow Symphony - Science and Education
http://www.rainbowsymphony.com/scied.html
Resources:
                DIFFRACTION GRATING MATERIALS
                Rainbow Symphony Inc.
                6860 Canby Ave.  #119
                Reseda, CA  91335
                Tel: (818) 708-8400
                Fax: (818) 708-8470 
                Toll Free: (800) 821-5122
                           Rainbow Symphony Inc.
                Email: Kathy@rainbowsymphony.com

Difraction Gratings for Spectroscopy and Telecom
http://www.jyinc.com/oem3/gratings.htm

Multi-function Optics - MEMS Optical
http://www.memsoptical.com/prodserv/products/multi-func.htm

Short of accelerating the light source to relativistic speeds,
shifting a spectral section seems an unlikely-to-succeed experiment.
Good luck.

SEARCH TERMS

liquid crystal shutter
liquid crystal shutter manufacturer
liquid crystal shutter spectroscopy
liquid crystal "optical phased array" spectroscopy
liquid crystal "optical phased array" spectrometer
liquid crystal "optical phased array" manufacturer
Raytheon

hlabadie-ga

very detailed information. It was a very hard question as I was
looking for a solution to a problem, not just an answer. I think this
will provide it. Thank you.

It's very frustrating that I cannot answer this question because I am
not a researcher an I cannot be, but I know the answer (or I am close
to the answer)!

"I want to be able to shine the light through the prism and have
600nm wave length come out of the prism at angle X, then change the
optical density / refractive index (some how) so that I can have wave
length 700nm or 800nm etc come out at angle X (the same angle)."

What you are looking for is a filter system. You want to have a light
source (fixed color/wavelength) and have a variable output in terms of
color/wavelength. You need nothing more than disc attached to a finely
geared electric motor. As the disk spins a diffrent grade/color of
filter is moved in the path of the beam. Things of this sort are
sometimes used to precision color correction in video and film
reproduction. Some DOPs (Directors of Photography) get real picky
about the color rendition in their finished work. I see you're looking
for wavelengths outside of the visible spectrum and closer to infared.
There are a whole variety of glass based filters with steep cutoffs
and narrow bandpass that are USUALY used for scientific work in
conjunction with Infared Films. This may be a solution for you. All at
no charge from me to you. (Granted, I don't include a million links
like the paid answer-person either. You get what you pay for.)