PLUTO Phase Only Spatial Light Modulator (Reflective)
|PLUTO Spatial Light Modulator – Microdisplay Features|
|Display Type:||Reflective LCOS (Phase Only)|
|Resolution:||1920 x 1080|
|Pixel Pitch:||8.0 µm|
|Fill Factor:||87 % / 93 % (dependent on version)|
|Active Area||15.36 x 8.64 mm (0.7″ Diagonal)|
|Addressing||8 Bit (256 Grey Levels)|
|Signal Formats||DVI – HDTV Resolution|
|Input Frame Rate||60 Hz|
The PLUTO phase only Spatial Light Modulator (SLM) consists of a driver unit with standard digital video interface (DVI or HDMI) and a phase only LCOS (Liquid Crystal on Silicon) microdisplay with full HD resolution (1920 x 1080 pixel) and 8 µm pixel pitch leading to an active area diagonal of 0.7” with aspect ratio of 16:9.
The PLUTO SLM is a plug & play phase modulator device and can be addressed with phase functions via standard graphics cards as extended monitor device. The green color channel of the video signal is used for addressing 8 bit gray level patterns (the SLMs native resolution need to be addressed). Addressing can be done using the supplied Pattern Generator software or the SLM Slideshow Player software or standard image viewer software.
HOLOEYE offers different display versions that can be driven with the PLUTO driver unit. The different panel versions are optimized for the use at different wavelength ranges. All versions use fast full digital addressing which assures high reliability and a compact driver unit as basically only two voltages need to be generated. There are 2 driver versions available:
The standard PLUTO driver uses a DVI interface for addressing phase functions and an RS232 interface to communicate with the driver (to changing the voltage vs. gray level distribution (gamma control) and dynamic range (voltage across the LC cell) in order to calibrate the SLM for different wavelengths).
The enhanced PLUTO-2 driver uses an HDMI interface for addressing phase functions and an USB connection for advanced calibrations. Besides this the driver features a trigger sync output to synchronize the device with external devices. With the PLUTO-2 driver faster addressing is possible which enables to work in color-field-sequential (CFS) mode with color-switchable lasers. The increased addressing speed also reduces phase flicker effects.
The PLUTO-2 driver also features a dual-core ARM® Cortex™-A9 processor which also includes on-chip memory. This enables the user to program additional functionality which is directly processed on the PLUTO-2 device (e.g. a slideshow from images which are loaded from USB flash or from internal memory). The dual-core system runs an embedded Linux™ SMP operating system and includes a library which provides full control and supervision of the display and driver board. The PLUTO-2 provides access through Serial and Ethernet-over- USB2 (RNDIS) interfaces and can be programmed using standard Ubuntu™ cross compile GCC toolchain.
The PLUTO displays show a reflectivity of approx. 60%-75% (dpendent on version) and diffraction efficiencies of more than 80%. Thereby a total light efficiency of more than 50% per addressable diffractive device is possible.
PLUTO Phase Modulator Versions
Besides the standard PLUTO-VIS and PLUTO-NIR versions there are special high retardation versions available (-HR versions) which show a considerably higher phase retardation compared to the standard panels which enables more stable addressing or mod 4π respectively mod 6π phase functions to be addressed. This can be beneficial for wave front functions as this enables higher slopes and can reduce transition points in the addressed function compared to mod 2π encoding.
The pulse code modulation for digitally addressed devices leads to a slight superimposed phase flicker. For some applications a stable phase response is required. This can be accomplished driving the high retardation panels with low voltage settings for 2π phase retardation, however compromising the response time.
Some PLUTO SLM display versions are equipped with a dielectric mirror coating to increase the reflectivity. Due to the increased reflectivity less absorbtion occours and these display versions can be used with higher incident laser power compared to the standard versions.
|Version||Wavelength Range||Reflectivity||Max. Phase Shift||Comment||Recommendation|
|PLUTO-UV-043||350 – 420 nm||90 %||2.8 Pi @ 355 nm
2.3 Pi @ 405 nm
|Dielectric Mirror||UV resistance
Higher Power Use
|PLUTO-VIS-014||420 – 650 nm||65 %||3,9 Pi @ 530
2.9 Pi @ 650 nm
|Fast Response Time|
|PLUTO-VIS-016||420 – 650 nm||67 %||6,7 Pi @ 530 nm
5,4 Pi @ 633 nm
|High Retardation Version||Low Phase Flicker|
|PLUTO-VIS-020||530 – 640 nm||75-80 %||8,2 Pi @ 530 nm
6,3 Pi @ 633 nm
|High Phase Shift|
|PLUTO-VIS-056||450 – 650 nm||93 %||TBD||Dielectric Mirror||Higher Power Use|
|PLUTO-NIR-011||420 – 1100 nm||65-75 %||4,5 Pi @ 530 nm
2,6 Pi @ 850 nm
2 Pi @ 1064 nm
Fast Response Time
|PLUTO-NIR-015||650 – 1100 nm||65-73 %||4,4 Pi @ 850 nm
3,7 Pi @ 1064 nm
|High Retardation Version||Low Phase Flicker|
|PLUTO-NIR-002||1000 – 1100 nm||62 %||2 Pi @ 1064 nm|
|PLUTO-NIRO-023||1000 – 1400 nm||74 %||4,1 Pi @ 1400 nm|
|PLUTO-TELCO-013||1400 – 1700 nm||80 %||3,5 Pi @ 1550 nm|
PLUTO Spatial Light Modulator Kit – Contents:
|PLUTO Spatial Light Modulator – Scope of Supply|
|PLUTO SLM Driver Box|
|Phase Only Display incl. Flex Cable (1920 x 1080 Pixel)|
|DVI-cable & DVI/HDMI-adaptor|
|Serial Port Cable (RS232)|
|Power Supply (5V DC, 3A)|
|Operating Instruction / Manual|
|Data Medium (CD or USB Flash Drive) with Manual, User Software and Application Software and PLUTO Software Package|
PLUTO Phase Modulator – Software Features:
The PLUTO phase only modulator devices can simply be addressed like an external monitor using the standard DVI / HDMI interface of the graphics card. No additional software or dedicated hardware is needed to operate the SLM.
The device is delivered with a Configuration Manager software. The Configuration Manager can be used to change geometrical settings, brightness, contrast and the electrooptical response by applying a new gamma curve or another digital drive scheme. For these advanced callibrations the RS232 interface has to be connected via a COM port of the computer (there are also USB to COM adapters available).
In addition a HOLOEYE SLM Pattern Generator software is provided with the SLM. Key features of which are:
- Computation of computer generated holograms (CGH) from user defined images
- generation of SLM signals representing basic optical functions such as lenses, gratings, axicon and vortex functions
- superposition of CGH’s with basic optical functions to combine functionalities
Besides that, for LabView users a Labview SubVi for enhanced addressing of optical functions is included.
|PLUTO Software Features|
|SLM Configuration Manager||Brightness / Contrast / Geometry / Gamma Control|
|SLM Pattern Generator||Basic DOE computations; Generation of optical functions (Circular Aperture, Fresnel Zone Lens, Axicon, Single and Double Slit …); Gratings (incl. Blazed and Sinusoidal), superposition of functions (e.g. prisms, Zernike polynomials…)|
|SLM Slideshow Player||Plays slideshow of user defined precalculated functions or images|
|Labview SubVi||Labview SubVi for enhanced addressing of optical functions (for implementation in user defined Labview programm for e.g. closed loop applications)|
Driver Dimensions (Unit: mm):
Display Dimensions (Unit: mm):