Display device

Abstract

A display device has drive circuits each having a logic gate for inhibiting the inputting of a data signal from a signal line when unselected and permitting the inputting of a data signal from the signal line when selected, based on a drive signal (select voltage) applied from a select line, a capacitor for holding the output of the logic gate when selected and outputting the held output as a control voltage, and a drive voltage generating circuit for generating a drive voltage for displacing the actuator based on the control voltage from the capacitor.

What is claimed is:  
     
         1 . A display device comprising: 
 a display unit having actuators arrayed at respective pixels and displaceable for turning on and off the corresponding pixels;    a plurality of select lines for supplying instructions to select and unselect the pixels;    a plurality of signals lines for supplying pixel signals to the pixels which have been selected; and    a drive unit having drive circuits arrayed at respective pixels each for driving the corresponding actuator in response to an instruction from one of the select lines and a signal from one of the signal lines;    each of said drive circuits having: 
 a logic gate for inhibiting the inputting of a signal from said signal line when unselected and permitting the inputting of a signal from said signal line when selected, based on a select voltage applied from one of said select lines;  
 a capacitor for holding the output of said logic gate when selected and outputting the held output as a control voltage; and  
 a drive voltage generating circuit for generating a drive voltage for displacing said actuator based on said control voltage.  
   
     
     
         2 . A display device according to  claim 1 , wherein a binary output of a low logic voltage is used as said control voltage and said select voltage.  
     
     
         3 . A display device according to  claim 1 , wherein each of said actuators has a capacitive structure having a pair of electrodes, and said drive voltage generating circuit has a thin film transistor having a gate to which said control voltage is applicable and a drain connected to one of the electrodes of said actuator.  
     
     
         4 . A display device according to  claim 3 , wherein said thin film transistor comprises an array of small-size transistors, said small-size transistors having respective sources and drains connected in common and constructed as a single module for performing switching operation with a common gate signal.  
     
     
         5 . A display device according to  claim 1 , wherein each of said actuators has a capacitive structure having a pair of electrodes, and said drive voltage generating circuit comprises a push-pull circuit having a p-channel thin film transistor and an n-channel thin film transistor having respective gates to which said control voltage is applicable and connected in series to each other at a junction which is connected to one of the electrodes of said actuator.  
     
     
         6 . A display device according to  claim 5 , wherein each of said thin film transistors comprises an array of small-size transistors, said small-size transistors having respective sources and drains connected in common and constructed as a single module for performing switching operation with a common gate signal.  
     
     
         7 . A display device according to  claim 1 , wherein said logic gate comprises an analog switch.  
     
     
         8 . A display device according to  claim 1 , wherein said logic gate comprises a transfer gate.  
     
     
         9 . A display device according to  claim 1 , wherein at least said actuators are disposed on a first board and at least said drive unit is disposed on a second board, said first board and said second board being bonded to each other.  
     
     
         10 . A display device according to  claim 1 , wherein said display unit has a light waveguide panel for introducing therein light from a light source, and has a function to display an image depending on an image signal inputted thereto on said light waveguide panel by controlling said actuators to be displaced into contact with and away from said light waveguide panel depending on an attribute of said image signal, thereby to control leakage light from regions of said light waveguide panel.  
     
     
         11 . A display device comprising: 
 a plurality of actuators arrayed at respective pixels and displaceable for turning on and off the corresponding pixels;    a plurality of select lines for supplying select and unselect signals to the pixels;    a plurality of signals lines for supplying pixel signals to the pixels which have been selected; and    a drive unit having drive circuits arrayed at respective pixels each for driving the corresponding actuator in response to an instruction from one of the select lines and a signal from one of the signal lines;    each of said drive circuits having: 
 a transistor having a drain for being supplied with a signal from one of said signal lines and a gate for being supplied with a signal from one of said select lines, for applying a drive voltage to displace said actuator;  
 a capacitor for keeping said drive voltage when unselected at a constant level, said gate of the transistor and said select line being AC-coupled by said capacitor; and  
 a resistor connected between a junction between said gate of the transistor and said capacitor and the source of said transistor.  
   
     
     
         12 . A display device according to  claim 11 , wherein each of said thin film transistors comprises an array of small-size transistors, said small-size transistors having respective sources and drains connected in common and constructed as a single module for performing switching operation with a common gate signal.  
     
     
         13 . A display device according to  claim 11 , wherein at least said actuators are disposed on a first board and at least said drive unit is disposed on a second board, said first board and said second board being bonded to each other.  
     
     
         14 . A display device according to  claim 11 , wherein said display unit has a light waveguide panel for introducing therein light from a light source, and has a function to display an image depending on an image signal inputted thereto on said light waveguide panel by controlling said actuators to be displaced into contact with and away from said light waveguide panel depending on an attribute of said image signal, thereby to control leakage light from regions of said light waveguide panel.  
     
     
         15 . A display device comprising: 
 a plurality of actuators arrayed at respective pixels and displaceable for turning on and off the corresponding pixels;    a plurality of select lines for supplying reset, select, and unselect signals to the pixels;    a plurality of signals lines for supplying pixel signals to the pixels which have been selected; and    a drive unit having drive circuits arrayed at respective pixels each for driving the corresponding actuator in response to an instruction from one of the select lines and a signal from one of the signal lines;    each of said actuators having a capacitive structure having a pair of electrodes, one of said electrodes being connected to one of the select lines;    each of said drive circuits having a two-terminal nonlinear device connected between the other electrodes of one of said actuators and one of the signal lines.    
     
     
         16 . A display device according to  claim 15 , wherein at least said actuators are disposed on a first board and at least said drive unit is disposed on a second board, said first board and said second board being bonded to each other.  
     
     
         17 . A display device according to  claim 16 , wherein said select lines and said signal lines are disposed on said second board.  
     
     
         18 . A display device according to  claim 16 , wherein said drive voltage generating circuit has an open-drain circuit arrangement and has a pull-up resistor disposed on said first substrate.  
     
     
         19 . A display device according to  claim 15 , wherein said display unit has a light waveguide panel for introducing therein light from a light source, and has a function to display an image depending on an image signal inputted thereto on said light waveguide panel by controlling said actuators to be displaced into contact with and away from said light waveguide panel depending on an attribute of said image signal, thereby to control leakage light from regions of said light waveguide panel.  
     
     
         20 . A display device comprising: 
 a display unit disposed on a first board and having actuators arrayed at respective pixels and displaceable for turning on and off the corresponding pixels; and    a drive unit disposed on a second board and having drive circuits arrayed at respective pixels each for driving the corresponding actuator in response to an input signal;    said first board and said second board being bonded to each other;    said second board having at least one vent hole defined therein.    
     
     
         21 . A display device according to  claim 20 , wherein said display unit has a light waveguide panel for introducing therein light from a light source, and has a function to display an image depending on an image signal inputted thereto on said light waveguide panel by controlling said actuators to be displaced into contact with and away from said light waveguide panel depending on an attribute of said image signal, thereby to control leakage light from regions of said light waveguide panel.