The current trend is for some manufacturers to claim that infrared heat lamps are ‘extra low glare’. But what do they mean? How do they measure it? Light is measured in luminous flux or lumens, as we know, but the human eye has different sensitivity to different wavelengths; small amounts of blue often appear brighter than larger amounts of red. Lumens cannot be used in this instance and indeed the LIA themselves have not reached a conclusion on the measurement of glare.
Some manufacturers are simply allowing more red light to be emitted because of the lower sensitivity of the eye to red. I don’t think this is satisfactory; a red glowing beam is far from pleasant for alfresco wining and dining! Let’s see how new technology can solve this problem.