Journal of the Society of Motion Picture and Television Engineers (1950-1954)

Page scan 00013 from Journal of the Society of Motion Picture and Television Engineers

Record Details:

Title:
Journal of the Society of Motion Picture and Television Engineers
Date:
1950-1954
Publisher:
Easton, Pa. : The Society
Volume:
Journal of the Society of Motion Picture and Television Engineers
Leaf #:
00013
Language:
English
Collection:
Technical Journals
Format:
Periodicals
Contributor:
Prelinger Library
Sponsor:
MSN
Coordinator:
Media History Digital Library
Date Added:
July 19, 2022
Something wrong or inaccurate about this page? Let us Know!

Thanks for helping us continually improve the quality of the Lantern search engine for all of our users! We have millions of scanned pages, so user reports are incredibly helpful for us to identify places where we can improve and update the metadata.

Please describe the issue below, and click "Submit" to send your comments to our team! If you'd prefer, you can also send us an email to mhdl@commarts.wisc.edu with your comments.




We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.

Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.

CENTER LINE OF FILM FRAME APPARENT POSITION OF FILM FRAME Fig. 2. Geometric relationship between film and moving mirror in continuous projector. Fundamental Principles The basic principle of operation of the machine used as an optical projector is shown on Fig. 1. Film 3 is moved at a uniform rate by sprocket 4 down over curved gate 9. Light from lamp 1 passing through condensing lens 2 and film 3 is reflected by compensating mirror 5 through objective lens 6 and reflected from fixed mirror 7 to screen 8. As sprocket 4 is rotated to move film 3, mirror 5 is caused to rotate about axis 1 0 by cam 1 1 . The amount of rotation of mirror 5 is such that the image of the film on the screen produced by lens 6 remains stationary. The geometric relation between film 3 and the mirror 5 is shown in Fig. 2. Consider the horizontal line CO passing through the center of the aperture in gate 9 and the center of curvature O of gate 9, as a fixed horizontal optical axis; also the radial lines aO and bO passing through the centers of two adjacent film frames a and b of film 3 and point O to form an angle a. Also consider line dO as a fixed optical axis passing through point O and the nodal point d of objective lens 6. Finally consider the reflecting surface 5 of a mirror pivoted about point O. The requirement for optical compensation of the moving film is as follows: January 1952 Journal of the SMPTE Vol. 58