Indicating circuit for camera visually indicating need for flash exposures and periods of the exposures

Abstract

Abstract A CONTROL CIRCUIT FOR USE IN A CAMERA HAVING AN ELECTRICALLY OPERATED SHUTTER INCLUDING A TIMING CIRCUIT THAT AUTOMATICALLY CONTROLS THE EXPOSURE TIME BY APPLYING A SWITCHING SIGNAL TO A SWITCHING CIRCUIT THAT CLOSES THE SHUTTER. THE TIMING CIRCUIT INCLUDES A LIGHT-RESPONSIVE DEVICE AND DEVELOPS THE SWITCHING SIGNAL AS A FUNCTION OF THE BRIGHTNESS OF THE SCENE BEING PHOTOGRAPHED. A MANUALLY OPERATED CHANGE-OVER SWITCH SELECTIVELY CONNECTS THE TIMING CIRCUIT TO THE SWITCHING CIRCUIT FOR ESTABLISHING A TIME EXPOSURE MODE OF OPERATION FOR TAKING TIME EXPOSURES AND DISCONNECTS THE TIMING CIRCUIT FROM THE SWITCHING CIRCUIT AND CONNECTS A FLASH CIRCUIT INTO THE CONTROL CIRCUIT FOR ESTABLISHING A FLASH MODE OF OPERATION. A CONNECTING SWITCH, ACTUATED BY THE CAMERA RELEASE, CONNECTS THE LIGHTRESPONSIVE DEVICE TO A WARNING AND INDICATING CIRCUIT. WHEN THE CHANGE-OVER SWITCH IS SET FOR THE TIME EXPOSURE MODE THE LIGHT-RESPONSIVE DEVICE APPLIES A BIAS SIGNAL TO A WARNING AND INDICATING CIRCUIT WHICH EMITS A WARNING SIGNAL TO WARN THE CAMERA USER THAT THERE IS INSUFFICIENT LIGHT AND THAT THE FLASH MODE OF OPERATION IS NECESSARY. A SYNCHRO-SWITCH IN THE FLASH CIRCUIT, ACTUATED BY THE RELEASE LEVER OF THE CAMERA, IS CLOSED WHEN THE SHUTTER IS OPENED AND IS OPENED AS THE SHUTTER CLOSES. IT CONTROLS THE IGNITION OF THE FLASH DEVICE WHEN THE CHANGEOVER SWITCH IS SET FOR THE FLASH MODE, AND CONTROLS THE EMISSION OF THE WARNING SIGNAL DURING THE TIME THE SHUTTER IS OPEN, WHEN THE CHANGE-OVER SWITCH IS SET FOR THE TIME EXPOSURE MODE.

Inventors

• 👤 T Murakami
• 👤 Y Nakamura
• 👤 E Onda
• 👤 Y Morino

Bibliographic Details