摘要:
A thermotropic chiral nematic liquid crystalline copolymer composition comprises ##STR1## wherein --NEM-- and --NEM'-- are each independently nematogenic units of formula ##STR2## wherein R is H or CH.sub.3, --Q-- is an alkylene radical having 1 to about 8 carbon atoms,--X-- is --O--, --S--, or --CH.sub.2 --, --Y-- is ##STR3## --Z is --CN, --NO.sub.2 or --N.dbd.C.dbd.S, q and r are each independently 0 or 1;wherein --CHI-- is a chiral unit of formula ##STR4## wherein R is H or CH.sub.3, --Q'-- is an alkylene radical having 1 to about 8 carbon atoms,--X'-- is --O--, --S--, or --CH.sub.2 --,--Z' is an alkoxy, aralkoxy, alkylamino, or aralkylamino radical having 4 to about 12 carbon atoms and containing at least one asymmetric carbon atom,q' and r' are each independently 0 or 1;and wherein x is the mole fraction of chiral units and (y+y') is the total mole fraction of nematogenic units in said copolymer composition, and the ratio of x to (y+y') is from about 1:50 to 1:1.This compolymer composition is employed to form an optical device.
摘要:
A glassy thermotropic chiral nematic liquid crystalline composition comprises a glassy chiral nematic compound of low molar mass that includes a cycloaliphatic radical, a nematogenic moiety, and a chiral moiety, or a mixture of a nematic liquid crystalline compound of low molar mass that includes a cycloaliphatic radical and a nematogenic moiety and a chiral compound of low molar mass that includes a chiral moiety. Each cycloaliphatic radical contains 4 to about 18 carbon atoms. An optical device is formed from the described glassy thermotropic chiral nematic liquid crystalline composition.
摘要:
A glassy thermotropic chiral nematic liquid crystalline composition comprises a glassy chiral nematic compound of low molar mass that includes a cycloaliphatic radical, a nematogenic moiety, and a chiral moiety, or a mixture of a nematic liquid crystalline compound of low molar mass that includes a cycloaliphatic radical and a nematogenic moiety and a chiral compound of low molar mass that includes a cycloaliphatic radical and a chiral moiety. Each cycloaliphatic radical contains 4 to about 18 carbon atoms. An optical device is formed from the described glassy thermotropic chiral nematic liquid crystalline composition.
摘要:
A projection system, a spatial light modulator, and a method for forming a MEMS device is disclosed. The spatial light modulator can have two substrates bonded together with one of the substrates comprising a micromirror array. The two substrates can be bonded at the wafer level after depositing a getter material andlor solid or liquid lubricant on one or both of the wafers. The wafers can be bonded together hermetically if desired, and the pressure between the two substrates can be below atmosphere.
摘要:
Disclosed herein is a micromirror device having in-plane deformable hinge to which a deflectable and reflective mirror plate is attached. The mirror plate rotates to different angles in response to an electrostatic field established between the mirror plate and an addressing electrode associated with the mirror plate.
摘要:
A releasing and post-releasing method for making a micromirror device and a micromirror array device are disclosed herein. The releasing method removes the sacrificial materials in the micromirror and micromirror array so as to enabling movements of the movable elements in the micromirror and micromirror array device. The post-releasing method is applied to improve the performance and quality of the released micromirrors and micromirror array devices.
摘要:
Speckle effect in display system is reduced by utilizing the instability of phase-coherent light and the transmission of the instable phase-coherent light through a multi-mode optical fiber with a suitable length.
摘要:
Processes for the removal of a layer or region from a workpiece material by contact with a process gas in the manufacture of a microstructure are enhanced by the ability to accurately determine the endpoint of the removal step. A vapor phase etchant is used to remove a material that has been deposited on a substrate, with or without other deposited structure thereon. By creating an impedance at the exit of an etching chamber (or downstream thereof), as the vapor phase etchant passes from the etching chamber, a gaseous product of the etching reaction is monitored; and the endpoint of the removal process can be determined. The vapor phase etching process can be flow through, a combination of flow through and pulse, or recirculated back to the etching chamber
摘要:
Processes for the removal of a layer or region from a workpiece material by contact with a process gas in the manufacture of a microstructure are enhanced by the ability to accurately determine the endpoint of the removal step. A vapor phase etchant is used to remove a material that has been deposited on a substrate, with or without other deposited structure thereon. By creating an impedance at the exit of an etching chamber (or downstream thereof), as the vapor phase etchant passes from the etching chamber, a gaseous product of the etching reaction is monitored, and the endpoint of the removal process can be determined. The vapor phase etching process can be flow through, a combination of flow through and pulse, or recirculated back to the etching chamber.
摘要:
The present invention teaches a method and apparatus for removing sacrificial materials in fabrications of microstructures using one or more selected spontaneous vapor phase etchants. The selected etchant is fed into an etch chamber containing the microstructure during each feeding cycle of a sequence of feeding cycles until the sacrificial material of the microstructure is exhausted through the chemical reaction between the etchant and the sacrificial material. Specifically, during a first feeding cycle, a first amount of selected spontaneous vapor phase etchant is fed into the etch chamber. At a second feeding cycle, a second amount of the etchant is fed into the etch chamber. The first amount and the second amount of the selected etchant may or may not be the same. The time duration of the feeding cycles are individually adjustable.