Optical scanner

• US 3,885,094 A
• Filed: 10/12/1973
• Issued: 05/20/1975
• Est. Priority Date: 11/26/1971
• Status: Expired due to Term

• Current Assignee: Optical Recording Corp.
• Original Assignee: James T. Russell
• Inventors: Russell, James T.
• Primary Examiner(s): Britton, Howard W.
• Assistant Examiner(s): Masinick, Michael A.
• Application Number:
  US05/405,770
• Time in Patent Office: 585 Days
• Field of Search: 178/7.6,6.7R,6.7A
• US Class Current: 359/205.1
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: H04N 3/08 having a moving reflector
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 5/85 on discs or drums

Abstract

An electrical signal recording and playback system is described in which an analog input signal is converted to a digital signal that pulses a light source to form a single, series-recorded track of binary coded digital information including information spots arranged in groups separated by synchronizing spots recorded on a photographic film which is played back in a similar manner. The photographic film is a compact, permanent record of long, useful lifetime which may be photographically copied to provide a plurality of inexpensive copies. A spiral track photographic record is used in one embodiment which can be employed to provide a music system of high quality. In one embodiment, a photographic record having bits arranged in lines or columns is held in a fixed position and a fan-shaped laser beam is moved horizontally over the record in a primary scan, and a row of microlenses focus line segments of the columns in seriatim on a row of photocells, the microlenses being stepped vertically from line to line in a vertical secondary scanning. In another embodiment, a laser beam is scanned horizontally and vertically to illuminate pages of information on a photographic element one after another, and, during the illumination of the pages, a matrix of lenslets, each covering one page, is scanned vertically over the height of a page, to transmit the lines of the illuminated pages seriatim to a row of photocells.

Claims

1. Optical scanner apparatus comprising:

a rotatable support, a resilient arm member fixed at one end to said support, a mirror attached to said arm member, motor means for rotating said support, deflection means for bending said arm member in response to an electrical control signal to radially move said mirror during rotation of said support in order to provide the mirror with a spiral-shaped scan track on an image plane, and compensation means for moving said mirror away from the image plane as said mirror is deflected radially inward along said scan track in order to maintain the optical path length between the mirror and the image plane substantially constant during scanning.

2. Scanner apparatus in accordance with claim 1 in which the deflection means includes an electromagnetic means for bending said arm member.

3. Scanner apparatus in accordance with claim 1 in which the motor means includes control means for varying the speed of rotation of said support so that the speed increases as the mirror is moved radially inward.

4. Scanner apparatus in accordance with claim 1 in which the arm member is a leaf spring and the mirror is attached to the leaf spring at a position aligned with the axis of rotation of the support.

5. Scanner apparatus in accordance with claim 4 in which the compensation means includes a weight attached to the free end of the spring on the opposite side of the axis of rotation from its fixed end.