SLM Thermal Management Systems
HOLOEYE Spatial Light Modulators are based on Liquid Crystal microdisplays. Physical properties of LC materials show a temperature dependence and a change in temperature may influence different optical SLM properties (phase shift, switching speed, phase stability…).
SLM displays have their own power dissipation, which varies between products and configurations. To keep the performance / temperature stable, an active thermal management system should be used.
HOLOEYE offers two different active thermal management systems. Both systems use a Peltier element for active temperature controlling. The TMS001 is equipped with a passive heat sink and the TMS 002 uses an actively water-cooled heat sink for higher temperature differences and higher power dissipation.
The HOLOEYE SLM Thermal Management Systems act as a display mount. The systems are designed to fit with the current versions of the HOLOEYE PLUTO-2, GAEA-2, LETO-3 and ERIS Spatial Light Modulator series. The systems are modular and can easily be exchanged dependent on requirements and applications.
TMS 001: Thermal Management System with Air-Cooled Heat Sink
The HOLOEYE Thermal Management System TMS 001 is based on a Peltier element (thermoelectric cooler) in combination with a passive heat sink and can both cool and heat up the SLM display.
Stabilization of the display temperature against ambient variation is enabled by an active temperature controller. However, the cooling capabilities of TMS 001 are rather limited by the amount of heat load the passive sink can reject to the surrounding air.
The TMS 001 typically is sufficient to stabilize the display temperature at room temperature when using an incident laser power of up to 10 Watt, depending on the reflectivity of the display. The TMS 001 is designed to operate at room temperature and to keep the display at constant temperature around standard display temperatures (30 °C – 35 °C) or to heat and stabilize the display to elevated temperatures (e.g. 65 °C).
TMS 001 Deliverables:
TMS 002: Thermal Management System with Water-Cooled Heat Sink
Even using HOLOEYE’s high reflectivity SLM versions (with dielectric mirror), an active thermal management system is required for high-laser power applications. The HOLOEYE Thermal Management System TMS 002 with an active water-cooled heat sink is especially designed for the use with higher laser power.
The TMS 002 uses water to cool the warm side of the Peltier element. It comes in a unit with water reservoir and fan cooled radiator, but can be connected to external water cooling installations, too.
The active cooling of the circulating water allows the system to temperature-control HOLOEYE displays to low temperatures even when a considerable amount of additional heat of several Watts is brought into the system by a high-power light source.
In contrast to the TMS 001 controller, the TMS 002 controller has built-in temperature setting controls, i.e. this system can be operated without a connection to a personal computer.