Measure/Projects/Lighted Graticule
Lighted Graticule
Introduction -- What is a graticule?
A graticule is a "scale on transparent material on the focal plane of a optical instrument for the location and measurement of objects" (Webster's Ninth Collegiate Dictionary, 1990, Merriam-Webster Inc, Springfield MA). Oscilloscopes traditionally light the graticule by illuminating its edges; the graticule material (typically acrylic plastic) "pipes" the light through itself. If the pipe ight hits a line scratched in the plastic's surface, the light bounces off the scratch and illuminates the line.
When doing experiments that involve measurements, such lines become almost mandatory. Indeed, I decided I had to breadboard one up (see the photo) in the course of designing a waveform generator. I wanted to make measurements of the extremes of voltage that an LM358A operational amplifier can output when operated from 5 volts. (It turned out to be roughly 0.5 to 3.1 volts just like the spec sheet and calculationsindicated.)
