Liquid crystal display panel manufacturing method

• US 6,023,313 A
• Filed: 08/18/1997
• Issued: 02/08/2000
• Est. Priority Date: 08/21/1996
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Hazama, Yoshikazu
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US08/912,774
• Time in Patent Office: 904 Days
• Field of Search: 349/95, 349/158
• US Class Current: 349/95
• CPC Class Codes: B32B 2305/55 Liquid crystals
• CPC Class Codes: B32B 38/1833 Positioning, e.g. registration or centering
• CPC Class Codes: G02F 1/1333 Constructional arrangements; Manufacturing methodsG02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133354 Arrangements for aligning or assembling substrates

Abstract

A liquid crystal display panel manufacturing method and an aligning apparatus for use in the method make it possible to precisely align an active matrix substrate and a counter substrate with high precision even if the two alignment marks thereon are substantially apart from each other. A clear image is formed by focusing a microscope onto an alignment mark on a counter substrate, captured into a video camera and output as a first image signal. The first image signal output from the video camera is temporarily stored in an image memory. Next, a clear image is formed by focusing the microscope onto an alignment mark on an active matrix substrate, captured into the video camera and output as a second image signal. The second image signal output from the video camera and the first image signal temporarily stored in the image memory are synthesized by an image synthesizing circuit, and then, displayed clearly on a monitor.

Claims

1. A method for assembling a liquid crystal panel display, comprising the steps of:

providing an imaging system having an image pick-up device with a variable focus and a display device on which images from said image pick-up device are displayed;

disposing a first substrate, having a display portion including a matrix of pixels and a first alignment mark, at an arbitrary distance from said image pick-up device;

disposing a second substrate, having a second alignment mark, between said image pick-up device and said first substrate at a respective arbitrary distance from said image pick-up device and said first substrate;

separately focusing said image pick-up device to a first focal length to obtain focused images of said first alignment mark and separately focusing said image pick-up device to a second focal length to obtain focused images of said second alignment mark;

simultaneously displaying said focused images of said first alignment mark and said focused images of said second alignment mark on said display device;

shifting at least one of said first substrate and said second substrate relatively so that at least a portion of said first alignment mark in at least one of said focused images of said first alignment mark coincides with at least a portion of said second alignment mark in at least one of said focused images of said second alignment mark; and

laminating said first substrate and said second substrate together while maintaining a predetermined distance therebetween.

2. A method as claimed in claim 1 wherein said focused images of said first alignment mark comprise a first image set and wherein said focused images of said second alignment mark comprise a second image set, and wherein the step of simultaneously displaying said focused images of said first alignment mark and said focused images of said second alignment mark on said display device comprises:

storing one of said first image set and said second image set, as obtained by said image pick-up device, as a stored image set;

displaying the other of said first image set and said second image set in real time on said display device, combined with said stored image set.

3. A method as claimed in claim 1 wherein the step of disposing a second substrate between said image pick-up device and said first substrate comprises providing said second substrate with a plurality of microlenses for gathering light onto said pixels of said first substrate.

4. A method as claimed in claim 3 comprising the additional step of providing a transparent plate over said microlenses on said second substrate.

5. A method as claimed in claim 4 wherein the step of laminating said first substrate and said second substrate together includes filling a cavity, having a cavity height, between said first substrate and said second substrate with liquid crystal material, and wherein said first focal length differs from said second focal length by at least a thickness of said microlenses, a thickness of said transparent plate, and said cavity height.