Definition - "Optical"
For the purposes of the scientific endeavor called Optical SETI, the word optical is not to be taken as a synonym for the word visible. The word optical is a superset of the ultra-violet, visible and infrared regimes of the electromagnetic spectrum and covers five decades of wavelength from the ultra-violet (0.01 µm) to the far-infrared (1 mm).
Optical SETI Correct
Visible SETI Correct
Infrared SETI Correct
Visible and Infrared SETI Correct
Optical and Infrared SETI Incorrect
This is the more modern definition of the word optical which is used today by photonics engineers and scientists. The use of this definition may give physicists and astrophysicists some pain, but it will avoid considerable confusion later. All presenters are requested to adhere to this guideline.