CRi Spatial Light Modulator

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CRi Spatial Light Modulator

Simultaneous phase and amplitude modulation of your VIS or NIR beam with no moving parts
These Spatial Light Modulators (SLMs) are based on proven industry-leading designs, and offer both single-mask and dual-mask configurations for phase, amplitude, or for simultaneous phase/amplitude pulse shaping.
The Cambridge Research & Instrumentation (CRi) Spatial Light Modulators (SLMs) are now a part of Meadowlark Optics. CRi collaborated with the Massachusetts Institute of Technology (MIT) on the initial development of modern liquid crystal (LC) SLMs, and is the exclusive worldwide licensee of MIT’s technology for bonded optical masks for simultaneous phase and amplitude control in a single device.
Liquid Crystal Optical Modulation
Our SLM optics use nematic LC to alter the phase or the amplitude of light. The LC masks provide an electrically variable index of refraction for light that is polarized along the crystal’s 'extraordinary” axis. The refractive index of light that is polarized along the “ordinary” axis (also called the orthogonal axis),
is not changed.
Depending on the orientation of the extraordinary axis of the LC mask and the placement of linear polarizers in front and/or behind the LC mask, a single-mask SLM can modulate a beam’s phase or amplitude.
The dual-mask models use a patented arrangement where two LC masks are bonded together in precise registration and proximity.  The masks are oriented orthogonal to one another and 45 degrees to the polarization of incident light.  This arrangement enables the independent adjustment of both phase and amplitude.  Removing the polarizers and driving both masks with the same patterns so the differential is zero allows the SLM to be used as a pure phase modulator for arbitrary polarized light.

  • Solid-state for rapid, vibration-free operation
  • Single-mask or dual-mask liquid crystal designs for phase, amplitude, or simultaneous phase/amplitude control
  • VIS or NIR wavelength ranges
  • Smaller SLM-128 enclosure for easier integration
  • USB interface with free Software Developer’s Kit (SDK) for efficient low-power operation and software integration

Specifications - CRi Spatial Light Modulator
  P128/A128 D128 P640/A640 D640
Number of Masks 1 2 1 2
Pixels per Mask 128 128 640


Pixel Height 5000 µm (5mm)
Pixel Pitch 100 ± 0.005 µm
Inter-Pixel Gap 2.0 µm
Inter-Mask Alignment - ± 2.0 µm - ± 2.0 µm
Inter-Mask Separation - 1.03 mm - 1.03 mm
Spectral Range 488 - 900 nm (VN models), 900 - 1620 nm (NM models)
Transmission VN Model > 88% > 85% > 88% > 85%
Transmission NM Model >92% >90% >92% >90%
Pulse Damage Threshold 100 µJ/cm2 (490 nm, 50 fs, 1kHz), 200 µJ/cm2 (890 nm, 50fs, 1kHz)
Maximum Modulation 3π radians at longest wavelength
Modulation Temp. Coefficient -0.3% modulation per oC
Response Time 35 ms (2π radians at 900 nm - VN model), 70 ms (2π radians at 1620 nm - NM model)
Drive Waveform Bipolar 3.3 kHz square wave
Drive Resolution 12 bit, 2.44 mV per step
Frame Buffers 128 32
Interfaces USB 1.1, 5V/3.3V logic trigger (TTL compatible)
Power +24V DC, via universal adapter (included)
Mechanical Housing 3 x 1/4" - 20 and 2 x M6 threaded holes
Overall Size 5.29" x 6.90" x 0.98" 7.2" x 12.8" x 1.54"
Operating Temperature 18 oC to 35 oC
Storage Temperature -15 oC to 50 oC
Please specify a wavelength when placing your order.
See page 3 of datasheet for a detailed description of specifications.


For ordering information, please contact  Sales at 303.833.4333 or