| 摘要 |
PURPOSE:To measure the quantity of incident light accurately in an optical device mounted with a transmission type electrochromic (EC) display body, for example, a camera, by correcting the decrease in the quantity of detected light that arises when the display body makes displaying (coloring). CONSTITUTION:A transmission type EC display body (a) is provided in a part of the section A of an optial path roughly at a right angle to the optical path, and the characters EC are displayed. The EC signifies, for example, the completion in charging of a strobe, the completion in winding of a film, or the date. According to the transmission conditin of an electric signal W1 to be fed from an EC display circuit G to the EC display body (a), the voltage signal W2 of the logical level of high or low is fed to a comparator D, by which the signal is converted to a correcting voltage for analog quantity. The correcting component is subtracted from the reference potential of the comparator D. Even when the EC is displayed, the quantity of detected light at which the EC is not displayed is displayed on a display E, and is recognized by an observer through a finder F2. |
