Micro-electro-mechanical systems element array device and image forming apparatus

Abstract

A micro-electro-mechanical systems element array device in which plural micro-electro-mechanical systems elements each having a movable portion are arranged in an array, said movable portion being to be displaced by a physical force which is generated by applying an electric signal to a conductive portion, and each of said micro-electro-mechanical systems elements drives and displaces said movable portion of said micro-electro-mechanical systems element on the basis of a displacement data for said micro-electro-mechanical systems element, wherein said device comprises: an electric signal generating unit as defined herein; a switching unit as defined herein; and a selecting unit as defined herein.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the configuration of two elements of a micro-electro-mechanical systems element array device which is an embodiment of the invention.

FIG. 2 is a view illustrating four waveforms of a control voltage signal generated by a control-voltage generating circuit shown in FIG. 1.

FIG. 3 is a view illustrating four kinds of elements of the micro-electro-mechanical systems element array device shown in FIG. 1.

FIG. 4 is a view showing a logical table of selection which is performed by a selecting circuit shown in FIG. 1.

FIG. 5 is a timing chart illustrating the operation of the micro-electro-mechanical systems element array device shown in FIG. 1.

FIG. 6 is a perspective view of two elements of a rotational displacement SLM element array which is an example of a two-dimensional micro-electro-mechanical systems element array device.

FIG. 7 is a diagram of the rotational displacement SLM element shown in FIG. 6.

FIG. 8A is a view showing an ON state of the SLM element shown in FIG. 7.

FIG. 8B is a view showing an OFF state of the SLM element shown in FIG. 7.

Claims

1. A micro-electro-mechanical systems element array device in which plural micro-electro-mechanical systems elements each having a movable portion are arranged in an array, said movable portion being to be displaced by a physical force which is generated by applying an electric signal to a conductive portion, and each of said micro-electro-mechanical systems elements drives and displaces said movable portion of said micro-electro-mechanical systems element on the basis of a displacement data for said micro-electro-mechanical systems element, wherein said device comprises: an electric signal generating unit which is disposed commonly to said micro-electro-mechanical systems elements; a switching unit disposed for each of said micro-electro-mechanical systems elements, said switching unit being for connecting said electric signal generating unit to said conductive portion of said micro-electro-mechanical systems element and for disconnecting said electric signal generating unit from said conductive portion of said micro-electro-mechanical systems element; and a selecting unit disposed for each of said micro-electro-mechanical systems elements, said selecting unit being for opening and closing said switching unit on the basis of the displacement data, so as to apply the electric signal from said electric signal generating unit to said conductive portion through said closed switching unit.

2. The micro-electro-mechanical systems element array device according to claim 1, wherein said conductive portion comprises a first conductive portion for generating a physical force for displacing said movable portion to a first position, and a second conductive portion for generating a physical force for displacing said movable portion to a second position, and said switching unit comprises a first switching unit for connecting said first conductive portion to said electric signal generating unit and for disconnecting said first conductive portion from said electric signal generating unit, and a second switching unit for connecting said second conductive portion to said electric signal generating unit and disconnecting said second conductive portion from said electric signal generating unit.

3. The micro-electro-mechanical systems element array device according to claim 2, wherein said electric signal generating unit generates plural different control voltage signals, and applies the different control voltage signals to said first and second conductive portions.

4. The micro-electro-mechanical systems element array device according to claim 3, wherein the control voltage signals have a signal waveform which suppresses vibration that is produced by said movable portion at said second position or said first position when said movable portion is displaced from said first position to said second position, or from said second position to said first position.

5. The micro-electro-mechanical systems element array device according to claim 1, wherein the physical force is an electrostatic force or an electromagnetic force.

6. The micro-electro-mechanical systems element array device according to claim 1, wherein the displacement data is an image data.

7. The micro-electro-mechanical systems element array device according to claim 1, wherein said micro-electro-mechanical systems elements are optical modulation elements.

8. The micro-electro-mechanical systems element array device according to claim 1, wherein said electric signal generating unit is disposed commonly to at least micro-electro-mechanical systems elements of a same row.

9. An image forming apparatus which comprises the micro-electro-mechanical systems element array device according to claim 1.