Browse Prior Art Database

Measuring Aperture Camera

IP.com Disclosure Number: IPCOM000042470D
Original Publication Date: 1984-May-01
Included in the Prior Art Database: 2005-Feb-03
Document File: 2 page(s) / 39K

Publishing Venue

IBM

Related People

Moore, GM: AUTHOR

Abstract

This article describes and illustrates improvements to aperture cameras which reduce the time required to create apertures for use with artwork generators by simplifying some steps in the current process. An aperture camera is used to reduce by a factor of 10 an image master and place the reduced image on an aperture blank. Alignment of the master and blank is extremely important. The present camera design has a fixed aperture blank holding station. It occurs with some frequency that the master to be reduced is not easily rotationally alignable with the optical axis of the camera because of some defect in the master. Further, with the present design the user must expose a test blank and process it completely before measuring on a separate device for correct size alignment and rotation.

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Measuring Aperture Camera

This article describes and illustrates improvements to aperture cameras which reduce the time required to create apertures for use with artwork generators by simplifying some steps in the current process. An aperture camera is used to reduce by a factor of 10 an image master and place the reduced image on an aperture blank. Alignment of the master and blank is extremely important. The present camera design has a fixed aperture blank holding station. It occurs with some frequency that the master to be reduced is not easily rotationally alignable with the optical axis of the camera because of some defect in the master. Further, with the present design the user must expose a test blank and process it completely before measuring on a separate device for correct size alignment and rotation. In the figure, which is a schematic representation of the upper portion of a known aperture camera, additions are indicated which eliminate the above described problems. Lens 2 is provided for reducing the image of the master (not shown). A rotational aperture stage 6 is provided. Beam splitter 8 is placed between the reduction lens 2 and the aperture stage 6. This stage is calibrated to allow precise rotation. A calibrated reticle is positioned at 10 so that a user may measure size, alignment and rotation prior to a complete processing operation. The beam splitter may be permanently positioned or may be selectively positioned for removal during exposure....