Image display apparatus and image display module
View Patent ↗An image display apparatus configured by a display panel having an image memory element in a pixel, which achieves low power consumption. A nonvolatile image memory element 1 , which can change the resistance value by phase change, is connected to a pixel electrode 25 of a liquid crystal element 5 . The output of a thin-film transistor 17 driven by scanning and signal electrode lines 7, 9 is connected to the pixel electrode 25 . When the scanning electrode line 7 is selected to have a high level voltage, the thin-film transistor 17 is turned on and a current signal flowing through the signal electrode 9 is sent through the image memory element 1 to a reference electrode line 15 . Depending on the current value or pulse width passing through the image memory element 1 , the resistance of the image memory element 1 is changed and is stored as a resistance value. A liquid crystal drive voltage to be applied to the liquid crystal element 5 is varied depending on the resistance of the image memory element 1 and an image is displayed on the liquid crystal element 5.
1. An image display apparatus comprising:
an image display panel having a display element comprising a plurality of pixels arranged in a matrix at crossing points where a plurality of scanning electrode lines cross a plurality of signal electrode lines;
a scanning electrode line selection circuit for selecting the scanning electrode lines of the image display panel;
a signal electrode line drive circuit for driving the signal electrode line;
storage means for storing display data for each pixel, said storage means comprising:
memory element electrode,
a phase change film in contact with the memory element electrode, and
a resistor connected to each pixel; and
a switching element for controlling the display state of the display element provided for the pixel, said switching element being a TFT including a gate electrode,
wherein:
the display data is stored in the pixel by way of the resistance value of the resistor,
the storage means is a non-volatile memory,
storage means is capable of rewriting the stored display data in a nonvolatile manner such that the stored display data does not change in the absence of power,
the display state of the display element is controlled by controlling the switching element using a voltage that changes in accordance with the resistance value of the storage means,
the switching element is turned on/off based on changes in the resistance value of the storage means, and
the gate electrode and the memory element electrode have higher melting points than the phase change film.
2. The image display apparatus according to claim 1 , further comprising means for reading the display data stored in the storage means.
3. The image display apparatus according to claim 2 , further comprising:
an operating means for comparing the display data read from the storage means by the reading means with display data to be subsequently displayed,
wherein:
the read display data is compared with the display data to be subsequently displayed and the storage means is rewritten with the display data to be subsequently displayed only when the display data are different,
the storage means is provided within the pixel,
the operating means is provided outside of the image display panel,
the operating means includes a line memory for storing one scanning line of image data, and
the line memory holds display data read from the storage means by the reading means.
4. The image display apparatus according to claim 2 , wherein each pixel has a plurality of the storage means, the apparatus further comprising means for selecting the storage means.
5. The image display apparatus according to claim 1 , further comprising:
a resistor,
wherein a voltage determined by resistive division by the storage means and the resistor is applied to the switching element.
6. The image display apparatus according to claim 1 , wherein the gate electrode and the memory element electrode are formed with identical material.
7. The image display apparatus according to claim 1 , wherein the TFT includes a source electrode,
wherein the source electrode is formed on the phase change film, and
wherein the width of the phase change film at the side of the memory element electrode is narrower than the width of the phase change film at the side of the source electrode.
8. The image display apparatus according to claim 1 , wherein the image display panel includes a recording apparatus that records display data, and the recording apparatus is configured to be detachable.