Active matrix liquid crystal display with identification mark in the lower opaque conductive film

DETAILED DESCRIPTION It is an object of the present invention to provide a liquid crystal display device in which an identification mark can be readily viewed from the surface thereof so that control of product such as process control and reliability control can be sufficiently achieved.
In order to accomplish the above-mentioned object, the present invention provides an active matrix type liquid display device including a display pattern unit formed on a glass substrate, comprising an identification mark portion formed on a blank portion of said display pattern unit excepting display and terminal areas thereof, said identification mark portion including an opaque thin film provided with identification mark and formed on said glass substrate, said opaque thin film with identification mark being coated with a transparent thin film thereon.
The identification mark portion is formed inside of a cutting line for separating individual devices provided on the glass substrate.
The opaque thin film provided with the identification mark is a lower metal film formed immediately upper side of the glass substrate.
The identification mark includes a bar code in addition to the identification characters.
The identification mark portion is formed of the opaque thin film provided with the indentification mark by using, for example, a lot of the lower metal wires formed immediately below the glass substrate in the blank portion excepting the display area and the terminal area of the display pattern portion.
Only the transparent thin film is formed on the opaque thin film area with the identification mark.
Accordingly, the identification mark can be confirmed from the surface of the device so that the control of the device is facilitated.
Each discrete device can be added with the identification mark by forming the identification mark portion inside of the cutting line of the device to facilitate the control of the reliability of the devices.
Control of the devices can be further facilitated by marking a bar code as the identification mark in combination with the character pattern