Ring laser gyroscope

About: Ring laser gyroscope is a research topic. Over the lifetime, 2070 publications have been published within this topic receiving 18609 citations. The topic is also known as: Sagnac interferometer.

Laser Gyro Technology

Abstract: The technology of the laser gyro has advanced to where production of this unique gyro withlow cost and high performance is now possible. The technology of lifetime and its factorshave now shown operating lifetime capability in excess of 50,000 hours. The performancevariation with wavelength and size shows the wide range of parameters which must be con-sidered. The performance of the laser gyro in scale factor linearity varies from 0.1% in thesmall 9.8 cm 1.15p gyro to better than 0.0001% in the 43 cm 0.63p gyro. In similar fashionthe null stability and performance also varies over a range of 10 ° /hr to 0.01 ° /hr for thesame gyros, respectively. Other factors such as gas pressure and multi mode effects are alsodiscussed.IntroductionThe laser gyro has been in the research and development stage since 19621 and the firstdemonstration in 19632. In the years since the development of the technology to implementthis exciting concept to practical use as an inertial instrument has required an advancedtheoretical understanding and analysis of the He -Ne laser and associated extensive experi-mental investigations and advanced construction and assembly techniques to achieve lifetimeand low cost. In the past two years the experimental and theoretical results show that thisdevice will challenge conventional gyroscopes in many applications.The basic principal of the laser is quite simple, i.e., a closed path, rotating in inertialspace, will have a path length which is slightly larger in the direction of rotation andshorter when traveling around the path against the direction of rotation. This path differ-ence is proportional to the input rate. The laser gyro utlizes this phenomena to measureinertial motion by having two laser oscillators operating around the cavity. One of these isclockwise and one counter -clockwise. Since the frequency of the oscillator will adjust tothe path length the difference in frequency between the two oscillators is a direct and linearmeasurement of the inertial input rate.This represents perhaps the only method of sensing inertial rate which does not use storedenergy in a rotating or vibrating mass. The lack of this mass property has been viewed asone of the principal features of the laser gyro as it permits inertial rotation measurementswith virtually no g or g2 effects.The technologies which have been involved in these years in order to achieve a practicaldevice have required excellent analytical work3'

Method of localization of leakiness of ring laser gyroscopes

Abstract: FIELD: measuring equipment.SUBSTANCE: glow discharge is excited in the laser gyroscope and the emission spectrum is recorded. Then the discharge is quenched and a sealed cap is subsequently installed on the gyroscope details, connected to the housing either by the method of an optical contact or through an indium seal. The indicator gas is supplied under the cap and maintained with excessive pressure for a predetermined time. After each setting and holding in the laser gyroscope, a glow discharge is again excited and the appearance of the spectral line of the indicator gas in the emission spectrum is recorded. The appearance of the spectral line of the indicator gas or the increase of its intensity indicates that the connection of this detail with the housing is leaking.EFFECT: ensuring the possibility of unambiguous localization of the source of leakiness.3 dwg

Multimode fibre laser gyroscope

Abstract: FIELD: measurement.SUBSTANCE: invention relates to laser measuring equipment. Multimode fibre laser gyroscope includes an annular laser consisting of an optical amplifier, an annular resonator in form of a coiled in a light guide coil, a phase modulator using which a frequency base is created, and an X-type fibre splitter, two ports of which serve to output a portion of radiation power of the ring laser, a device for combining waves output from the ring laser, a photodetector and an electronic system. Gyroscope also has a spectral-selective narrow-band filter installed in the ring laser.EFFECT: technical result is increased sensitivity of gyroscope.9 cl, 5 dwg

Mirror of a ring laser gyroscope

Abstract: The present invention relates to a mirror for a ring laser gyroscope and, more specifically, to a mirror for a ring laser gyroscope which prevents damage to a mirror surface by plasma and ultraviolet radiation by optical coating. The mirror for a ring laser gyroscope comprises: a first reflection film (200) formed on one surface of a substrate (100) by alternately and sequentially depositing a tantalum oxide layer (210) and a silica layer (220) which are formed in an optical thickness of one fourth of a wavelength () of incident light of a gyroscope and have different refractive indices; and a second reflection film (300) deposited on an outermost surface of the first reflection film (200) and made of a material durable against plasma active ions to block ultraviolet radiation to protect a surface. The first reflection film (200) is designed to reflect a wavelength of a band of 600-800 nm, and the second reflection film (300) is designed to reflect a wavelength of a band of 200-350 nm. The second reflection film (300) consists of an alternate layer wherein a zirconium oxide (ZrO2) layer and an aluminum oxide (Al2O3) layer are alternately formed. The zirconium oxide (ZrO2) layer and the aluminum oxide (Al2O3) layer are formed in an optical thickness of (0.4 ~ 0.43)/4 of the wavelength () of incident light. An aluminum oxide (Al2O3) layer with an optical thickness of (0.8 ~ 0.86)/4 is formed on an outermost portion of the second reflection film (300) to have an optical thickness which is two times thicker than each layer making up the second reflection film.