Showing papers on "Waveplate published in 1983"

Comparison type dimension measuring method and apparatus using a laser beam in a microscope system

Abstract: A comparison-type dimension measurement system in which a laser 1 provides linearly polarized light that is directed by a polarization beam splitter 5 into a microscope system in which a specimen 13 is mounted. The reflected polarized light is rotated 90° by a quarter wave plate 9 and passes through the beam splitter to a multi-element line sensor 19. The laser light is scanned by a rotatable mirror 3 over the specimen. Threshold intensities are determined on indicia of known separation on a reference specimen and used to calibrate the distance measured by the line sensor.

Magnetic field measuring device

Abstract: A magnetic field measuring device comprises a laser light source delivering laser light having two components of first and second frequencies; a beam splitter for dividing the laser light into two portions; a quarter wave plate provided to receive one portion of the laser light; a Faraday rotator provided to receive the output of the quarter wave plate and rotates the polarized direction thereof by an angle corresponding to a magnetic field applied thereto; first and second optical analyzers for extracting from the other portion of the laser light and the output of the Faraday rotator, first and second components of an equal frequency corresponding to the difference of the first and second frequencies, respectively; first and second photoelectric converters for converting the outputs of the first and second optical analyzers into first and second electric signals, respectively; and circuitry for comparing the first and second electric signals thereby to produce an output directly proportional to the magnetic field applied to the Faraday rotator.

Apparatus for detecting faults in transparent objects

Abstract: In a detecting system adapted to detect foreign matters as faults of a glass bottle, between a projection path of a diffused light towards the object to be inspected and said object, a plane polarizing plate of a circular polarizer which includes the plane polarizing plate combined with a 1/4 wave plate is disposed at the side of a diffused light side, while, in a light path which causes light transmitted through the object to form an image on the photoelectric detector 6 through the lens, a detecting side circular polarizer which includes a 1/4 wave plate and a plane polarizing plate is placed. An output electric signal of the photoelectric detector is subjected to analog operation processing.

Isolated pump in a double pass pump Raman oscillator and optimum conversion of pump energy in a Raman oscillator and amplifier

Abstract: A radiation pump recovery system for a double pass pump Raman oscillator is described incorporating a polarizer and quarter waveplate positioned in the optical path of the input pump radiation and functions to separate the reflected pump radiation coming back from the Raman oscillator along the input optical path from said input optical path. In an alternate embodiment the recovery system may include an additional quarter waveplate and mirror to permit unpolarized pump radiation to be separated into two polarizations to drive two Raman oscillators and whereby the reflected pump radiation coming back from the Raman oscillators along the respective input optical paths is separated from said respective input optical path and recombined into a single beam. An alternate embodiment utilizes the rejected pump energy in a Raman amplifier to provide optimal conversion efficiency. The oscillator which may be single pass pump or double pass pump Raman oscillator and amplifier utilize a common Raman active gas in a common housing having windows to provide separate optical paths for the oscillator and amplifier.

Scattering of circularly polarized radiation

Abstract: The differential refraction and absorption of circularly polarized light was applied by Henry Eyring and co-workers to study the configuration and conformation of small molecules. The differential scattering as a function of angle of circularly polarized light can provide structural information about large scattering systems. We present the general equations relating circular differential scattering to the eigenfunctions of a scatter which is of arbitrary size relative to the wavelength of light. An equiv experiment is to measure the ellipticity of the scattered light when linearly polarized light is incident.

Optical device for reproducer

Abstract: PURPOSE:To make the size of a device small, by transmitting a light beam emitted from a polarized beam splitter after introducing the beam to the polarized beam splitter again and making the beam incident to a photodetector provided in the vicinity of the other end of the polarized beam splitter. CONSTITUTION:A light from an optical source 1 is irradiated on a recording medium 6 via a beam splitter 2, a 1/4 wavelength plate 4, and an objective lens 5, the reflected light is led to the beam splitter 2 from the objective lens 5 and the plate 4 inversely, and reflected at the splitter 2 orthogonally and irradiated to a mirror 11 and a photodetector 9 via a 1/4 wave plate 10. The reflected light with the mirror 11 is irradiated to a photodetector 12 via the plate 10 and the splitter 2 to obtain a focusing servo signal from the detector 12 and a tracking servo signal from the photodetector 9. Thus, small size and light weight can be realized.

Measuring apparatus of surface stress

Abstract: PURPOSE:To measure surface stress accurately, by a method wherein a laser beam is excited to run in parallel with a surface of an object to be measured, and surface stress is measured by utilizing a senarmount compensator according to the difference of photoelastic beam pathes arisen in the emitted beam. CONSTITUTION:A laser beam 8 emitted from a light source 29 is reflected at a prism 38 and reached to a glaze layer A of an object B to be measured. The beam further advances in the layer A, and then, a part of the beam passes through an exit prism 26, and through a quarter wave plate 43 which forms a senarmount compensator with a polarizing plate 32B, and is detected by a photodetector plate 47. When there is stress, it is observed as the contracted part 316 in a streak of light 313 by rotating the plate 47. The stress can be measured on the basis of the Senarmount law, by measuring the shift of the shadowed part 311 which is shifted as the plate 47 rotates.

Light scattering by bubbles in liquids: comments and application of results to circularly polarized incident light

Abstract: Recently published Mie theoretic computations of the scattering of linearly polarized light from a bubble in water also apply, in certain cases, to the scattering of circularly polarized incident light. A correction to the labeling of one of the figures in the paper by Marston, Langley, and Kingsbury is noted.

Polarized light absorption of the magnetic semiconductor CdCr2Se4

Abstract: The absorption of polarized light in CdCr2Se4 thin films in the spectral region 10000 to 22000 cm−1 at different temperatures is investigated. Through the whole spectral region the absorption intensity differs for right-handed and left-handed circularly polarized light or for parallel and perpendicular linearly polarized light. The character of the temperature and polarization dependence of the absorption intensity is different for different parts of the spectrum. The observed absorption is considered as a sum of the interband transitions and the transitions between localized states. [Russsian Text Ignored.]

Endoscope device equipped with control means for quantity of incident light

Abstract: PURPOSE:To remove halation and blooming, and handle a subject which has a part where the quantity of incident light is small locally by controlling the quantity of incident light from a highlight part to a proper value even for the subject. CONSTITUTION:A polarizing plate 13 is supported pivotally near iris positions on both optical paths in front of an objective lens 3 and a light distribution lens 6, and a quarter-wavelength plate 14 is arranged further before it; and the polarizing plate 13 has its angle theta of rotation controlled by a rotation driving means 15. The polarizing plate 13 has the axis beta of polarization normally at 90 deg. to the crystal axis alpha of the quarter-wavelength thin plate 14 containing the optical axis of uniaxial crystal; and illumination light passed through the light distribution lens 6 at said angle or almost at the angle is passed through the polarizing plate 13 to pass only its linear polarized light polarized in the direction of the axis beta of polarization, and the polarized light is further passed through the quarter-wavelength plate 14 to shift the phase of the component polarized in the direction of the crystal axis alpha by 45 deg., but this component is zero or almost zero to irradiate a subject side with the linear polarized light.

Optical data discriminating device

Abstract: PURPOSE:To branch optical data efficiently by making the optical data which is desired to branch incident as parallel polarized light to a groove of a relief type diffraction grating in advance among multiplexed optical data and making others incident as orthogonal polarized light. CONSTITUTION:Multiplexed optical data is emitted from an optical fiber 24 for input to form an image on a surface relief type diffraction grating 18 formed on a transparent substrate 15 through a lens 25. Polarized light (S polarized light) parallel to a groove of the diffraction grating 18 is diffracted, and made incident to branching optical fibers 29, 31, 33 and 35 through lenses 28, 30, 32 and 34. On the other hand, P polarized light vertical to the S polarized light advances straightforward, and is made incident to an output use optical fiber 27 through a lens 26. An optical signal which is desired to branch is made incident as the S polarized light in advance, and others are made incidnent as the P polarized light. In this way, the optical data is branched very efficiently.

Optical information recording device

Abstract: PURPOSE:To surely and accurately stop an objective lens at its focussing position, by stopping the displacement of the objective lens toward a recording medium when an output obtained by detecting the reflected light of a laser light for detection with a split detector exceeds another output obtained by detecting and amplifying the laser light with a detector and an amplifier CONSTITUTION:A linear motor 3 and objective lens 10 approach a recording medium 2 through a vertical movement mechanism 19 under the control of a control circuit 21 An optical beam B coming out from a detection laser 11 is split into two parts by a half mirror 24 after passing through a lens 12 and one half of the optical beam B is made incident on a photodetector 25 and the other half of the beam B is converged onto the recording medium 2 of a disk 1 after passing through a polarization beam splitter (PBS)13, lambda/4 wave plate 14, mirror 9, and objective lens 10 The reflected light of the optical beam B advances in the reverse direction and is made incident on a split detector 15 The output of the split detector 15 is compared with the output of the detector amplified by an amplifier 27 at comparators 22 and 23 and, when the output of the split detector exceeds the output of the amplifier 27, the objective lens 10 is surely and accurately stopped at its focussing position through the controller 21