Modelling the optical pathway of the Large Binocular Telescope

2012 ◽  
Author(s):  
Michael Böhm ◽  
Thomas Ruppel ◽  
Jörg-Uwe Pott ◽  
Oliver Sawodny ◽  
Tom Herbst ◽  
...  
Keyword(s):  
Optical Pathway

Mathematical modelling of remote detection of molecular air pollutants

1987 ◽  
Vol 52 (6) ◽  
pp. 1397-1406
Author(s):  
František Zrcek ◽  
Milan Horák
Keyword(s):  
Atmospheric Aerosols ◽  
Air Pollutants ◽  
Complex Refractive Index ◽  
Mie Scattering ◽  
Heat Emission ◽  
Remote Detection ◽  
Radiation Absorption ◽  
Variable Concentration ◽  
Lidar Equation ◽  
Optical Pathway

A model of remote detection of molecular air pollutants is devised based on the lidar equation. The various kinds of interaction of radiation with matter, viz. absorption, induced fluorescence, and Raman scattering, are taken into account; detection of either scattered or reflected signal is considered. The reflection is assumed to be either axial, using a retroreflector, or omnidirectional from a field target. Based on this model, an algorithm was set up for simulation of the different variants of the experiment, making allowance for a generally variable concentration of the compound along the optical pathway of the light beam. The basic atmospheric processes, viz. radiation absorption by the backround, heat emission, turbulence, and the effect of atmospheric aerosols, are treated, and the last of them is found to play the major role. Aerosols are looked upon as a source of the Mie scattering and they are described by distribution equations with respect to the particle size and the complex refractive index. The variable concentration of the aerosol along the optical pathway and the simultaneous effect of a higher numberof aerosol types are included.

A Versatile Method of Optical Pathway Intervention for Experiments with Birds

Bird Behavior ◽  
1981 ◽  
Vol 3 (3) ◽  
pp. 96-101
Author(s):  
Graham A. Bell ◽  
John D. Ritchie
Keyword(s):  
Optical Pathway

Combining Multimodal Wavefront Examination and Digital Refraction to Create a Rapid and Accurate Approach (XFraction) for a Total Visual System Assessment for Intraocular Lens Selection

2013 ◽  
Vol 06 (02) ◽  
pp. 110
Author(s):  
Farrell C Tyson ◽  
Mitchell A Jackson ◽  
Jonathan D Solomon ◽  
◽  
◽  
...  
Keyword(s):  
Clinical Practice ◽  
Visual System ◽  
Intraocular Lens ◽  
Treatment Strategies ◽  
Relevant Information ◽  
Patient Diagnosis ◽  
System Assessment ◽  
Practice Efficiency ◽  
Diagnostic Technologies ◽  
Optical Pathway

Following advances in intraocular lens technology in recent years, greatly increased options are now available to the ophthalmic surgeon. However, there is a need for improved diagnostic technologies to optimize outcomes and select the best treatment strategies. A process combining multimodal wavefront examination and digital refraction, wavefront optimized refraction or ‘XFractionSM,’ has been recently developed to address this requirement. This novel fusion of techniques increases the amount of data that can be captured from each eye by orders of magnitude and is completed in much less time than former separate methods or manual refraction alone. The result is a process that enhances current procedures, provides superior patient diagnosis over previous techniques through the full optical pathway, and provides multiple benefits to both the patient and physician. The process enables the collection of a large amount of relevant information that makes available new levels of understanding about each patient’s unique visual system. Its use in clinical practice has been further associated with increased practice efficiency, enhanced optimized refractions, improved diagnostic surgical outcomes, and higher levels of patient satisfaction.

The eye of the soldier beetle Chauliognathus pulchellus (Cantharidae)

1979 ◽  
Vol 203 (1153) ◽  
pp. 361-378 ◽  
Keyword(s):  
Cross Section ◽  
Focal Plane ◽  
Optical Axis ◽  
Field Size ◽  
Acceptance Angle ◽  
Corneal Surface ◽  
Physiological Properties ◽  
Cone Cells ◽  
Optical Pathway ◽  
Surface Calculation

The soldier beetle eye is unusual in having large optically isotropic corneal cones which project inwards from a thick isotropic cornea. Refraction is mainly at the corneal surface. Calculation shows that the first focal plane is near the tip of the cone, from which the optical pathway continues as a crystalline tract. At the distal end of the crystalline tract, 3 µm in diameter, the four cone cells enclose the proximal tip of the corneal cone; at the proximal end they enclose the distal tip of a long fused rhabdom rod. The eye is remarkable in that there are two classes of retinula cells; four cells contribute to the long thin axial rhabdom, 2 µm in diameter and 120 µm long, and the other four cells form two rounded rhabdoms, 10 x 4 µm in cross-section and 20 µm deep, which lie to one side of the optical axis. The physiological properties of individual retinula cells were measured by intracellular recording. The retinula cells are of three spectral types with peaks near 360, 450 and 520–530 nm. Except by the criterion of spectral sensitivity, the retinula cells sampled could not be sorted into more than one class. The measured value of the acceptance angle, near 3° in the dark-adapted state, is consistent with the hypothesis that all sampled cells were of the anatomical type that participate in the central rhabdom rod. A calculation of the theoretical field size of individual retinula cells from measurements of refractive index and lens dimensions predicts that cells which participate in the central rhabdom will have acceptance angles near 3°. The conclusion, therefore, is that only one anatomical type of cell has so far been sampled.

High-resolution Neutron Diffraction using Larmor Precession

1998 ◽  
Vol 31 (5) ◽  
pp. 742-747
Author(s):  
W. H. Kraan ◽  
C. T. Kaiser ◽  
M. Th. Rekveldt
Keyword(s):  
High Resolution ◽  
Phase Shift ◽  
Neutron Beam ◽  
Fourier Transformation ◽  
Small Range ◽  
Diffraction Experiment ◽  
Reference Region ◽  
Larmor Precession ◽  
Set Up ◽  
Optical Pathway

A polarized neutron beam travels through a precession coil with fieldBand the intensity in a detector behind the analyser is recorded as a function ofB. Fourier transformation of the intensity signal gives the wavelength spectrum of the beam entering the detector. Any (diffraction) experiment can be set up in the optical pathway between the analyser and detector. This technique is applied in an array of high-resolution diffraction experiments along the path of the neutron beam through a bent Al strip. The detector intensities are measured only over a small range ofBaway from B=0. The phase shift between the intensity signals from compressed/extended regions, relative to the signal from a reference region in the strip, reveals the deformation of the Al lattice.

Effect of the optical pathway instability in a delay line on the intensity of the accumulated photon echo

1994 ◽  
Vol 61 (5-6) ◽  
pp. 768-772
Author(s):  
A. N. Yashin ◽  
A. P. Lazar' ◽  
S. B. Rutkevich
Keyword(s):  
Delay Line ◽  
Photon Echo ◽  
Optical Pathway

New trend on open solar photoreactors to treat micropollutants by photo-Fenton at circumneutral pH: Increasing optical pathway

2020 ◽  
Vol 385 ◽  
pp. 123982 ◽  
Author(s):  
Elizangela P. Costa ◽  
Melina Roccamante ◽  
Camila C. Amorim ◽  
Isabel Oller ◽  
José A. Sánchez Pérez ◽  
...  
Keyword(s):  
Optical Pathway ◽  
Circumneutral Ph

Alternatives to superposition images in clear-zone compound eyes

1971 ◽  
Vol 179 (1055) ◽  
pp. 97-124 ◽  
Keyword(s):  
Scattered Light ◽  
Retinula Cell ◽  
Compound Eyes ◽  
Clear Zone ◽  
Light Effect ◽  
Angular Sensitivity ◽  
Dim Light ◽  
Optical Pathway ◽  
Receptor Layer

The clear zone between the cones and the receptor layer in dark -adapted eyes of insects that are active in dim light has formerly been explained as a space to allow formation of a superposition image. Although erect images have been seen in Ephestia (Lepidoptera) and Hydrophilus (Coleoptera), new experiments show that they are accompanied by scattered light and that the angular sensitivity of individual receptors must be wide in the dark-adapted state. Alternatives to the superposition theory are examined, and it is concluded that in eyes with crystalline cones the clear zone (in general, in the numerous shapes and sizes of eyes of nocturnally active insects) enables light entering by many facets to sum upon individual receptors on the far side of the clear zone. In addition to the scattered light effect, light is carried across the clear zone in crystalline tracts or retinula cell columns, which provide a separate optical pathway for each ommatidium also in the light-adapted state.

scholarly journals Diagnosis, treatment and follow-up of patients with acromegaly in a clinical practice setting in Spain: the ACROPRAXIS program Delphi survey

Pituitary ◽  
2019 ◽  
Vol 23 (2) ◽  
pp. 129-139
Author(s):  
Pedro de Pablos-Velasco ◽  
Eva María Venegas ◽  
Cristina Álvarez Escolá ◽  
Carmen Fajardo ◽  
Paz de Miguel ◽  
...  
Keyword(s):  
Glucose Tolerance Test ◽  
Residual Tumor ◽  
Somatostatin Analogues ◽  
Tolerance Test ◽  
Delphi Survey ◽  
Oral Glucose ◽  
Full Agreement ◽  
Clinical Practice Setting ◽  
Optical Pathway

Abstract Aim The ACROPRAXIS program aims to describe the management of acromegaly in Spain and provide guidance. Methods Ninety-three endocrinologists were organized into 13 panels to discuss the practical issues in managing acromegaly. Based on the key learnings, an online Delphi survey with 62 statements was performed, so those statements achieving consensus could be used as guidance. Statements were rated on a 9-point scale (9, full agreement; consensus > 66.6% of response in the same tertile). Results Ninety-two endocrinologists (98.8%) answered two rounds of the survey (mean age 47.6 years; 59.8% women; median 18.5 years of experience). Consensus was achieved for 49 (79%) statements. Diagnosis: The levels of insulin-like growth factor I (IGFI) is the preferred screening test. If IGFI levels 1–1.3 ULN, the test is repeated and growth hormone (GH) after oral glucose tolerance test (OGTT) is assessed. A pituitary magnetic resonance is performed after biochemical diagnosis. Treatment: Surgery is the first treatment choice for patients with microadenoma or macroadenoma with/without optical pathway compression. Pre-surgical somatostatin analogues (SSA) are indicated when surgery is delayed and/or to reduce anaesthesia-associated risks. After unsuccessful surgery, reintervention is performed if the residual tumor is resectable, while if non-resectable, SSA are administered. Follow-up First biochemical and clinical controls are performed 1–3 months after surgery. Disease remission is considered if random GH levels are < 1 µg/L or OGTT is < 1 or ≤ 0.4 µg/L, depending on the assay’s sensitivity. Conclusion Current clinical management for acromegaly is homogeneous across Spain and generally follows clinical guidelines.

scholarly journals Normal patterns of déjà experience in a healthy, blind male: Challenging optical pathway delay theory

2006 ◽  
Vol 62 (3) ◽  
pp. 246-249 ◽  
Author(s):  
Akira R. O’Connor ◽  
Christopher J.A. Moulin
Keyword(s):  
Optical Pathway
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