Interferometric modulation of radiation
AssigneeIridigm Display Corporation
InventorMark W. Miles
Life of this patent
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Abstract
An Interferometric Modulator (IMod) is a microelectromechanical device for modulating light using interference. The colors of these devices may be determined in a spatial fashion, and their inherent color shift may be compensated for using several optical compensation mechanisms. Brightness, addressing, and driving of IMods may be accomplished in a variety of ways with appropriate packaging, and peripheral electronics which can be attached and/or fabricated using one of many techniques. The devices may be used in both embedded and directly perceived applications, the latter providing multiple viewing modes as well as a multitude of product concepts ranging in size from microscopic to architectural in scope.
Claims10
A modulator of light comprising:
- a substrate;
- a plurality of modulation elements formed on the substrate each modulation element defining an interference cavity for causing interference modulation of the light to produce a color condition when in a quiescent state, wherein the modulation element is of at least two types each having a different color condition when in the quiescent state, which color condition is a result of a spatial configuration of the modulation element.
An interference modulation device, comprising:
- a plurality of interference modulation elements fabricated on a substrate, each interference modulation element comprising a primary mirror and a secondary mirror which cooperate to interferometrically modulate incident light to produce a response in a quiescent state which response is determined by a spacing between the mirrors, wherein the interference modulation elements are of at least two types, each producing a different response in the quiescent state;
- and
- a driving mechanism to apply a bias voltage to each interference modulation element to cause the mirrors to be spaced apart the quiescent state, wherein each type of interference modulation element has a configuration that allows it to move to its quiescent state under influence of the same bias voltage.
A method for fabricating a modulation device, the method comprising:
- fabricating a plurality of interference modulation elements on a substrate, each interference modulation element comprising a primary mirror and a secondary mirror which cooperate to interferometrically modulate incident light to produce a response when in a quiescent state, which response is determined by a size of the a gap between the mirrors, the interference modulation elements being of at least two types, each having a different size gap and hence response when in the quiescent state, the fabricating including:
- depositing a uniform thickness sacrificial spacer material to space the primary and secondary mirrors during the fabrication process;
- altering a spatial configuration of each type of interference modulation element so that under influence of a uniform bias voltage, the secondary mirror of each type of interference modulation element is displaced to a position corresponding to the quiescent state for that type of interference modulation element;
- and
- removing the sacrificial spacer material.
Dependencies are inferred from the claim text.