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Maréchal intensity formula for small-Fresnel-number systems
Optics Letters, 1983A simple modification of the known Maréchal intensity formula is proposed. It enables one to evaluate the near the-diffraction-focus intensity distribution for well-corrected optical systems with small Fresnel numbers of the focusing geometry. As an example, the focal-shift effect in perfect systems is briefly reexamined.
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Dependence of focal shift on Fresnel number and angular aperture
Optics Letters, 1998The effect of angular aperture on the focal shift in optical systems of finite Fresnel number is considered. It is shown that the focal shift for a given Fresnel number decreases with increasing angular aperture.
C J, Sheppard, P, Török
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Focal switch: a new effect in low-Fresnel-number systems
Applied Optics, 1996It is shown for the first time we believe, that when a spherical wave illuminates a certain type of diffracting screen, in addition to the expected focal-shift effect, depending on the value of the Fresnel number of the focusing system, a focal switch effect can appear, i.e., an increase in the height of the lateral lobe of the axial-intensity ...
M, Martínez-Corral, V, Climent
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Toric concave mirror laser resonator with a big Fresnel number
Optics Letters, 2009A new type of toric concave mirror laser resonator with a big Fresnel number is presented. The M2 factor of an output laser beam of the new resonator with a Fresnel number of 8.05 is close to that of the plane-concave stable resonator with a Fresnel number of 2.01, the volume of output mode of the new resonator is about four times of that of the plane ...
Qin, Yingxiong +8 more
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Delay-time statistics in superfluorescence for large Fresnel numbers
Physical Review A, 1983A probability distribution for the delay time of superfluorescent pulses is calculated as a function of the Fresnel number from the solution of the linearized Maxwell-Bloch equations in three dimensions.
Jan Mostowski, Bożena Sobolewska
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PROPERTIES OF UNSTABLE RESONATORS WITH LARGE EQUIVALENT FRESNEL NUMBERS
Soviet Journal of Quantum Electronics, 1972The results are given of numerical calculations of oscillation modes in unstable resonators. It is shown that slight smoothing of the mirror edges leads to a considerable improvement of the selective properties of a resonator. It is shown that, contrary to the predictions of the theory of unstable resonators with sharp-edged mirrors, oscillation in the
V E Sherstobitov, G N Vinokurov
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Imaging in optical systems of finite Fresnel number
Journal of the Optical Society of America A, 1986Imaging, rather than focusing, in systems of finite Fresnel number is considered. Incoherent systems, coherent systems, and scanning systems are discussed. Scanning systems exhibit spatially invariant imaging, while for conventional systems, coherent imaging is necessarily space variant.
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Optical demonstration of a starshade at flight Fresnel numbers
Techniques and Instrumentation for Detection of Exoplanets VIII, 2017A starshade is a specially designed opaque screen to suppress starlight and remove the effects of diffraction at the edge. The intensity at the pupil plane in the shadow is dark enough to detect Earth-like exoplanets by using direct imaging. At Princeton, we have designed and built a testbed that allows verification of scaled starshade designs whose ...
Stuart B. Shaklan +7 more
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Pattern formation in a large Fresnel number dye laser
Optics Communications, 1995Abstract The early results of the first experimental study of pattern formation in a high Fresnel number dye laser (class A laser) are presented. It was observed that patterns complicate with increasing Fresnel number up to some value close to 20, after which they tend to simplify.
Silvia Gabriela Chuartzman +2 more
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Resonant Modes of Optic Cavities of Small Fresnel Numbers
Journal of the Optical Society of America, 1965A self-consistent perturbation method is developed for the determination of the normal modes and eigenvalues of optic cavities of small Fresnel numbers. The method permits direct determination of the field distribution and eigenvalue (i.e., the diffraction loss and resonant frequency) of a normal mode of any given order to within any desired accuracy ...
Leonard Bergstein, Harry Schachter
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