Optical measuring apparatus for measuring objects on machines

A method for making measurements of a rotating object and for producing an output, using an optical measuring apparatus which includes a light source which generates a beam of light and a detector for receiving the beam of light, comprising:

• rotating the object;
• causing a beam of light to be emitted from the light source;
• displacing the object transversely relative to the beam;
• detecting an extent of the beam of light at the detector while the object is being displaced transversely relative to the beam;
• generating a signal from the detector when a predetermined extent of light is present at the detector;
• delaying the output for at least one revolution of the object following the generation of the signal, and;
• causing an output to issue from the apparatus only if the signal is present at the detector at the end of the delay.

A method for making measurements of a rotating object and for producing an output, using an optical measuring apparatus which includes a light source which generates a beam of light and a detector for receiving the beam of light, comprising:

• rotating the object;
• causing a beam of light to be emitted from the light source;
• displacing the object transversely relative to the beam;
• detecting an extent of the beam of light at the detector while the object is being displaced transversely relative to the beam;
• generating a signal from the detector when a predetermined extent of light is present at the detector;
• causing a clock pulse to start, having a duration substantially equal to at least one revolution of the object, each time a signal from the detector is generated;
• and delaying the output until the end of the clock pulse.