A laser is a common term nowadays but do you know what it means? Laser stands for Light amplification by stimulated emission of radiation. Laser rangefinders have found an ever-increasing application and particularly in the military and communication systems. Laser rangefinders use laser radiation in the ultraviolet, visible and infrared range of the spectrum. The different radiation offers different ranging capabilities.
An understanding of the fundamentals of a rangefinder is essential as it determines the possible hazards while handling or using the device. The color of the beam produced by the rangefinder depends on the frequency or the wavelength of the laser beam. Shorter wavelengths mean the device is using ultraviolet radiation while longer wavelengths are for infrared radiation.
Components of a rangefinder
A laser rangefinder has three major components namely the lasing material, the pump source and the optical cavity. The lasing material can either be a crystal, a semiconductor diode, a dye or gas. The origin of the radiation beam is the excitation of electrons in the lasing material which are excited from their normal steady-state low energy level to a higher energy level by a flash lamp. The flash lamp is the source of power that adds energy to the lasing material initiating the excitation. After the beam has been produced, the optical cavity which consists of reflectors provides a feedback mechanism for light amplification.
Laser rangefinder uses the principle of an auto-focus camera to send a laser beam to and from the subject at a distance. In order to give a clear focus on the target, the ranging device offers some magnification allowance by incorporating a binocular in it.
To a rangefinder user, it is important to know that, the readings obtained from a device may differ from period to period depending on the prevailing environmental conditions. Remember that the device uses a beam of light, and intensity of light depends on the climatic conditions as well as the reflectivity of the target. So understanding the fundamentals of this tools is very important before using it.