China
Africa
Explore chapters and articles related to this topic
Parallel Transport and the Calculation of Retardance
Published in Russell A. Chipman, Wai-Sze Tiffany Lam, Garam Young, Polarized Light and Optical Systems, 2018
Russell A. Chipman, Wai-Sze Tiffany Lam, Garam Young
In a non-polarizing optical system, at reflections and refractions, no polarization state change occurs—only a change of direction. It is equivalent to the Fresnel amplitude coefficients being equal to one, as = ap = 1. The incident polarization ellipse, which is arbitrary, folds about the s-basis vector and continues with the same ellipse with the same major axis rotated. For refraction, the helicity of the state remains the same, right circularly polarized light refracts as right circularly polarized light. For reflection, there is an inversion of helicity, right circularly or elliptically polarized light reflects as left circularly or elliptically polarized light, associated with the change of the propagation direction. Thus, for the non-polarizing optical system, the polarization state only undergoes a series of rotations at reflections and changes of helicity. Figure 17.3 shows left elliptically polarized light propagating through a Dove prism, which has been ray traced as a non-polarizing optical system. At the entrance face, the polarization ellipse rotates with the propagation direction. Without other changes, it propagates to the bottom surface where it reflects as right elliptically polarized light. Finally, it rotates again following the refraction direction out of the Dove prism. This would be the evolution of the polarization state if all the Fresnel coefficients equaled one.
Optical Components
Published in Rajpal S. Sirohi, Mahendra P. Kothiyal, Optical Components, Systems, and Measurement Techniques, 2017
Rajpal S. Sirohi, Mahendra P. Kothiyal
Deviation prisms are classified in four groups according to the way they direct the optical axis in an optical system, (a) The optical axis remains unshifted in the entrance and exit spaces. Examples are the Dove prism and the two-components Amici prism, (b) The optical axes are parallel but shifted. The Fresnel rhomb and the porro-prism are examples. (c) The optical axis is deflected by 90°. Examples are the right-angle prism with hypotenuse as reflecting surface and its roof family and the pentaprism and its roof family, (d) The optical axis deflected by 45°. The Schmidt prism and its roof family are examples in this category. There are some prisms that deviate the optical axis by 30° and other angles.
Prism Design and Applications
Published in Paul Yoder, Daniel Vukobratovich, Opto-Mechanical Systems Design, 2017
The double-Dove prism comprises two Dove prisms, each of aperture A/2 by A, with their hypotenuse faces closely air spaced and parallel, resulting in a square aperture. This prism is commonly used as an image rotator or derotator in the same manner as described for the Dove prism. Figure 7.34 shows its configuration while Design Example 7.21 defines a specific design.
Corrections to the Raman fundamental band of N2 and O2 due to molecular non-rigidity: computations and experiment
Published in Molecular Physics, 2020
Jacek Borysow, Tyler Capek, Claudio Mazzoleni, Massimo Moraldi
All the experiments presented here were performed using a set-up shown in Figure 1. The major components of the Raman apparatus are: (1) A single mode CW 10W, fiber laser operating at 532 nm. (2) A pair of 50.2 mm diameter concave mirrors (SM) with 100 mm radius of curvature separated by 4 focal lengths in a multi-pass configuration. The nominal reflectivity of the mirrors at normal incidence is better that 99.99%. (3) A pair of collection lenses (,), which imaged the scattering region on to the entrance slit of the spectrograph. (4) Dove prism DP, the purpose of which is to rotate the light from the scattering region along the entrance slit of the spectrograph. (5) A long pass filter (LP) blocked the laser light from entering the spectrograph. The nominal optical density of LP at 532 nm was on the order of 6, and the transmission of LP in the spectral region of the oxygen and nitrogen Raman signals was approximately 98%. (6) A 0.5 m imaging spectrograph coupled to a cooled CCD camera operating at a temperature of C analysed the molecular spectra.
Phase discontinuities induced scintillation enhancement: coherent vortex beams propagating through weak oceanic turbulence
Published in Waves in Random and Complex Media, 2021
Hantao Wang, Huajun Zhang, Mingyuan Ren, Jinren Yao, Yu Zhang
Returning to the derivation of cross-spectral density, the analytical expression of T based on should be derived. Similar to the derivation of Rytov variance in Equation (13), T is also able to be transformed into the linear combination of and it can be written as Note that, for simplicity, the parameters associated with in the rest of this paper are just presented by the components associated with . Then, according to the integral formula [26] the result of Equation (4) is shown as follows: with where , and . represents the cross-spectral density of single beams with topological charges and is the cross-term of two beams. Using a Dove prism, these two beams can be generated by a Gaussian vortex beam with topological charge or topological charge [27]. Moreover, that can be achieved using a coherent Gaussian beam and a Dammann vortex grating generated by a spatial light modulator as well [28]. The same light source ensures that two beams are interfering beams.
Simultaneous multi-dimensional spatial frequency modulation imaging
Published in International Journal of Optomechatronics, 2020
Nathan Worts, John Czerski, Jason Jones, Jeffrey J. Field, Randy Bartels, Jeff Squier
The laser used as the illumination source for this microscope was an all-normal dispersion (ANDI) Yb-fiber oscillator[16] which has a central wavelength of 1040 nm. The microscope (Figure 8) consists of two identical 100 mm focal length cylindrical lenses () (Thorlabs LJ1567L1-B) that are placed after a polarizing beam splitter (PBS) (Thorlabs PBS253) in both the reflection and transmission directions. A half wave plate (HWP) is placed before the beam splitter to control the power in both arms of the microscope. The laser is focused by these lenses to the surface of the fused silica modulation mask (MM). Both arms 1 and 2 are then re-imaged in a 4-f configuration by 75 mm focal length lenses () (Thorlabs LA1145-B) which are placed 2f (150 mm) from the substrate. Arm 1 has a 50 mm lens () (Thorlabs LA1131-B) placed away from the image plane by its focal length, while Arm 2 consists of two 100 mm focal length lenses () (Thorlabs LA1509-B). The first of which is placed 43 mm from the image plane, and the second is separated from the first by 78.8 mm. This results in an effective focal length of 35.97 mm. Arm 2 also has an uncoated N-BK7 dove prism (DP) (Edmund Optics 32–553) with a clear aperture of 15 mm. This prism is rotated to an angle of with respect to the vertical direction, which rotates the modulated beam by The beams from each arm of the microscope are then recombined and made co-linear with another polarizing beam splitter (Thorlabs PBS253). The beams are imaged to the sample plane by an objective lens with a focal length of 125 mm (OBJ) (Thorlabs LA1384-B). In the current geometry with the dove prism at a angle, the two beams incident on the sample form an orthogonal cross pattern (Figure 7(b,i)), with the central points of each beam overlapped. If desired, the prism in Arm 2 may be rotated to any angle to rotate the beam by the desired arbitrary amount, or one beam may be moved relative to the other (as in Figure 7(b,i–iii)). When the image is made in the transmission direction, a 75 mm focal length lens () (Thorlabs LA1145-B) is placed behind the sample and focuses the light onto a photodiode where the temporal data is collected and processed to form the final images.