| 摘要 |
An exposure meter comprises exposure detecting means connected with an electric power source and including a photoelectric element, means connected with the photoelectric element to introduce exposure influencing factors thereinto, and means connected with the photoelectric element and with the introducing means to produce a proper exposure signal. Indicating means is connected with the exposure detecting means and operable to indicate a proper exposure in response to the proper exposure signal. Means is connected between the exposure detecting means and the indicating means to render the indicating means inoperable for any voltage drop of the source voltage below the minimum usable voltage.
|
