Self-testing mechanism determining X-ray exposure

摘要

A mechanism/device (29) in association with a radiographic cassette (20) in which X-ray film (28) or the like is exposed. Upon exposure, an LED (39) continually blinks, indicating exposure to the user, thereby obviating double exposure of the film. A test and reset circuit (80) informs the user at any time of the operational status of device (29). Device (29) comprises a sensor (30), a photodiode (47), a conduit formed by a bundle (31) of optical fibers which conveys light energy from sensor (30) to photodiode (47) that converts it into an electrical current controlled by an electronic circuit (35) which includes LED (39). Circuit (35) includes a detecting and amplifying circuit (51), an oscillating circuit (68), a latching circuit (65) for maintaining blinking of LED (39), and the test-and-reset circuit (80).