Microscopic observation and laser-controlled microoptothermal drive mechanism

The mechanism of novel optothermal microactuators (OTA) was analyzed with a microscope system, a charge-coupled device-combined light microscope, and a computer system. One OTA, two optothermal microswitches (OTS) with different length and shape were machined by an excimer laser micromatching system using single layer material. They all had two thin expansion arms with different widths. The mechanism of the OTA/OTS is that the different optothermal expansion controlled by asymmetric topology and shape of the arms causes a magnified lateral deflection or vibration. A red laser diode (650 nm) with maximum power output of 30 mW was employed as the external power source to drive the OTA/OTS. Experiments were carried out with the microscope system, and serial images and videos were acquired. The results indicate that the structure of the OTA/OTS is simple and easy to be manufactured. They can practically generate an obvious lateral deflection or vibration. When the location of the laser spot on the OTA changed, the direction of its deflection is also changed. When the value of laser power that irradiated on the OTS increased, the lateral deflection of the OTS enlarged, the maximum could be larger than 30 microm. This kind of novel microactuator has the advantages of remote wireless controlling, large displacement, simple structure, easy to be machined, and therefore will be quite useful for the practical applications in the fields of micro/nanotechnology.