GB864759A - Improvements in or relating to photographic printing apparatus - Google Patents

Improvements in or relating to photographic printing apparatus

Info

Publication number
GB864759A
GB864759A GB2067057A GB2067057A GB864759A GB 864759 A GB864759 A GB 864759A GB 2067057 A GB2067057 A GB 2067057A GB 2067057 A GB2067057 A GB 2067057A GB 864759 A GB864759 A GB 864759A
Authority
GB
United Kingdom
Prior art keywords
oscillators
spot
difference
july
photographic printing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB2067057A
Inventor
George Stanley Elphick
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bush and Rank Cintel Ltd
Original Assignee
Bush and Rank Cintel Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bush and Rank Cintel Ltd filed Critical Bush and Rank Cintel Ltd
Priority to GB2067057A priority Critical patent/GB864759A/en
Publication of GB864759A publication Critical patent/GB864759A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus
    • G03B27/725—Optical projection devices wherein the contrast is controlled electrically (e.g. cathode ray tube masking)

Landscapes

  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Physics & Mathematics (AREA)
  • Particle Formation And Scattering Control In Inkjet Printers (AREA)

Abstract

864,759. Automatic frequency control systems. BUSH & RANK CINTEL Ltd. July 1, 1958 [July 1, 1957], No. 20670/57. Drawings to Specification. Class 40(5) [Also in Group XL(b)] In apparatus in which a travelling spot on a C.R.T. is used for photographic printing and in which the light passing through the negative and printing paper falls on a photo-cell which controls spot intensity, the spot is deflected by a pair of oscillators each controlling the deflection in one co-ordinate direction and "pulling" between the oscillators is avoided by feeding the output of both oscillators to a mixing circuit to produce a difference frequency signal which is rectified and fed to one of the oscillators to maintain the difference constant. Where a sawtooth is produced by an oscillator of the type in which a condenser is alternately charged and discharged, the difference signal may be applied to the grid of a valve to control the charging or discharging rate.
GB2067057A 1957-07-01 1957-07-01 Improvements in or relating to photographic printing apparatus Expired GB864759A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2067057A GB864759A (en) 1957-07-01 1957-07-01 Improvements in or relating to photographic printing apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2067057A GB864759A (en) 1957-07-01 1957-07-01 Improvements in or relating to photographic printing apparatus

Publications (1)

Publication Number Publication Date
GB864759A true GB864759A (en) 1961-04-06

Family

ID=10149716

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2067057A Expired GB864759A (en) 1957-07-01 1957-07-01 Improvements in or relating to photographic printing apparatus

Country Status (1)

Country Link
GB (1) GB864759A (en)

Similar Documents

Publication Publication Date Title
ES454498A1 (en) Feedback control for laser discharge system
JPS57111116A (en) Comparator having hysteresis
JPS5746675A (en) Power circuit
GB864759A (en) Improvements in or relating to photographic printing apparatus
GB1483796A (en) Clamp circuits
US2751520A (en) Power supply regulation
GB740873A (en) Improvements in or relating to circuit arrangements for use in telecinematograph transmitters
GB1477887A (en) Particle concentration control apparatus
JPS5397756A (en) Amplifier circuit
JPS55607A (en) Frequency discriminator
GB842573A (en) Improvements in or relating to photographic printing apparatus
GB714442A (en) Automatic frequency control circuits
JPS5773429A (en) Parallel operation system of switching power supply
GB661807A (en) Television film scanning apparatus
ES8106634A1 (en) Regulated deflection circuit with start-up control.
JPS56117422A (en) Forming circuit of triangular wave signal
JPS54127608A (en) Input signal identification circuit
JPS566363A (en) Regulation of electron gun
JPS5576414A (en) Transless type switching constant voltage power unit
JPS54162036A (en) Conduction rate controlling circuit of contactless ignition apparatus
GB779912A (en) Improvements in or relating to methods and devices for making screened pictures
JPS5243436A (en) Control system for the copying machine
JPS55131283A (en) Power unit
GB931766A (en) Improvements in or relating to transistor d.c. convertors
JPS5441136A (en) Ink jet printer