1. Field of the Invention
The present invention relates to display apparatus and display method for performing displaying of an image using picture elements or “pixels” as disposed in a matrix fashion. In particular, the invention relates to a liquid crystal display device and EL display device of the active matrix type.
2. Description of the Related Art
Recently, the technology has been rapidly developed for fabrication of semiconductor devices with a semiconductor thin film being formed on a glass substrate of low cost, such as for example thin-film transistors (TFTs). The reason for this is that the needs for liquid crystal display devices of the active matrix type are increasing more and more.
The active-matrix type liquid crystal display device is such that TFTs are disposed respectively in several tens or several millions of pixel regions that are disposed in a matrix manner, which TFTs have their switching functions to control electrical charge carriers exiting from or entering to a respective one of pixel electrodes.
FIG. 1 shows a configuration of a liquid crystal display device of the active matrix type in the prior art. A shift register and buffer circuitry are typically called the “peripheral driver circuit” in general; in the recent years, this is integrally formed on the same substrate together with an active matrix circuit.
Disposed in the active matrix circuit are thin-film transistors which utilize amorphous silicon as formed on a glass substrate used.
A configuration has also been known wherein quartz is utilized as the substrate while employing a polycrystalline silicon film for fabrication of such thin-film transistors. In this case both the peripheral driver circuit and active matrix circuit will be constituted from those thin-film transistors formed on the quartz substrate.
In addition, a thin-film transistor fabrication technology is also known which makes use of a crystalline silicon film on a glass substrate by utilizing laser anneal techniques or the like. Use of this technology may enable integration of the active matrix circuit and its associated peripheral driver circuit on the glass substrate.
In the configuration shown in FIG. 1A, an image signal being supplied to an image signal line is selected at a timing as indicated by FIG. 1B in response to a signal from a shift register circuit (horizontal scanning shift register) of a source line side driver circuit. And, certain image signal will be supplied to a corresponding source signal line.
The image signal which was supplied to the source signal line is then selected by the thin-film transistor of a pixel to be written into a specified pixel electrode.
The pixel thin-film transistor is operable in response to a selection signal that is supplied via a gate signal line from a shift register (vertical scanning shift register) of a gate line side driver circuit not shown herein.
The above operation will be recurrently carried out with the setting of appropriate timings determinable depending on a signal from the shift register of the source line side driver circuit and a signal from the shift register of the gate line side driver circuit to thereby sequentially write information into respective pixels of the matrix shape.
After completion of writing of image information corresponding to a single screen, image information is then written for the next screen. In this way, displaying of images will be performed in a sequential order. Generally, such writing of this one-screen information is repeated for thirty times or alternatively sixty times per second.