With respect to MEMS (Micro Electro Mechanical Systems), along with refining the structure size from a micro-structure to a nano-structure, there is a tendency in which a drive energy supplying method with respect to a moving structure is a big problem.
In a MES structure of the prior art, as shown in the outlined figure of FIG. 14A, compared to the area of the moving mechanism, the size of the area shared by electric wiring for an electrostatic drive and a contact pad can be ignored; however, such as a variable grating of an Optical MEMS (David T. Amm and Robert W. Crrigan, “Optical Performance of the Grating Light Valve Technology”, Photonics West-Electronic Imaging 1999), if the structure size is approximately the same as a wavelength which is applied (a few μm), as shown in outline diagrams of FIGS. 14B and 14C, an area shared by the electric wiring respectively connected to the MEMS moving structure portion is relatively large and this is a problem for designing a function (special light modulation of diffracted light, intensity modulation, and the like) of a device.
As a solution for solving the above described congestion problem of the wiring, a laser manipulation, or a method which uses Maxwell stress in an electromagnetic field of radiated light has been discussed in the past. For example, by using changes of momentum of light (light pressure) which is caused along with refraction and incidence of the light into a semitransparent small object for a driving force, a position control, a rotation control, and the like of the small object which is suspended in liquid are operated (E. Higurashi, R. Sawada, T. Ito, “Optically driven angular alignment of microcomponents made of in-plane birefringent polyimide film based on optical angular momentum transfer” J. OF Microeng. Vol. 11(2), pp. 140-145, 2001).
Moreover, a method of causing a displacement by converting radiated optical energy to heat and combining this with the bimorph effect of the micro structure (S. Baglio, S. Castorina, L. Fortuna L. N. Savalli, “Modeling and design of novel photo-thermo-mechanical microactuators,” SENSORS AND ACTUATORS A101(1-2), pp. 185-193, 2002) is discussed as well.
However, compared to a conventional MEMS type electrostatic actuator to which a drive voltage can be arbitrarily set, the driving force generated from the light pressure or Maxwell force/stress of the light is very small; therefore, there is a problem in which it is difficult to simply replace the driving structure of the electrostatic actuator.
Moreover, with respect to the method of causing a displacement by converting radiated optical energy to heat and combining with the bimorph effect of the micro structure, a multiple layer structure is needed in an actuator portion; therefore, there is a problem in which the device structure is complex.
USPTO Backgrounds
USPTO Backgrounds