(n.) The science of the refraction of light; that part of geometrical optics which treats of the laws of the refraction of light in passing from one medium into another, or through different mediums, as air, water, or glass, and esp. through different lenses; -- distinguished from catoptrics, which refers to reflected light.
Example Sentences:
(1) Dioptric aniseikonia was calculated between 1 month and 24 months after surgery (with Gruber's and Huber's computer program) on the basis of most recently obtained values (bulb axis length, depth of the anterior chamber, lens thickness, necessary refraction), and compared with subjective measurements taken with the phase difference haploscope.
(2) Accommodation measurements of nine young, emmetropic subjects were obtained with an infrared optometer while they viewed superimposed horizontal and vertical square-wave gratings at various dioptric separations.
(3) The relationships between dioptric blur, pupil size, retinal eccentricity, and retinal sensitivity were investigated in the central 5 degrees of the visual field in 10 normal subjects using the Humphrey Field Analyzer.
(4) inhomogenities in the dioptric media, reflections at refracting surfaces, diffraction at the pupil borders, and the distribution of scattered light in the retina it becomes possible to develop indications for the construction of a focal optical stimulator.
(5) The elements of the dioptic power matrix have previously been interpreted in terms of power along particular meridians with the off-diagonal elements interpreted as a new form of dioptric power called torsional power.
(6) If the positions of the principal points of the crystalline lens are conjectured, its equivalent power and that of the eye can be calculated as described from ocular dioptrics.
(7) These ultra-thin soft lenses have proved extremely successful in case of visual defects ranging from - 16,0 to + 16,0 dioptrics.
(8) The dioptric elements in each ommatidium consist of a laminar cornea, which is flat externally and convex internally, and a bipartite crystalline cone.
(9) An alternative method for evaluating lens resolution is to determine the resolution efficiency (the relative percentage performance of a lens compared to a diffraction-limited lens of the same dioptric power).
(10) The former figure has the dioptric value M X sin2 alpha, the latter M X cos2 alpha.
(11) We analyzed 450 consecutive cases of intraocular lens implantation (omitting only two inadvertent implantations in patients with high myopia) to determine the dioptric lens power in each case required to produce emmetropia.
(12) The analysis contains four diagrams: a plot of the raw keratoscope data for quality control, a three-dimensional wire model of corneal surface power distribution, a plot of dioptric point surface powers, and a color-coded contour map of corneal surface powers.
(13) The eyelid fusion was temporarily cut and opened at about five-month intervals, and the dioptric power and axial length of test and control eyes were measured.
(14) Using both our own and published data, we compared the effects of diffusive blur, dioptric blur, and eccentric viewing on contrast sensitivity for letter and grating targets.
(15) They produce a magnified image, but it is an image that suffers from significant dioptric blur, diminished somewhat by use of a peep sight in the bowstring which functions as an aperture stop.
(16) The dioptric apparatus of each ommatidia includes a biconvex corneal lens and a spherical crystalline cone that is secreted by two cone cells.
(17) The eye consists of about 3600-3700 ommatidia, each containing a dioptric apparatus formed by a lamellated corneal lens and a eucone-type crystalline cone.
(18) We defined the depth of focus at a given spatial frequency to be the dioptric range for which the modulation transfer exceeds 50% of its peak value.
(19) Dioptric blur had a strong negative effect on Snellen acuity, consistent with previous studies, but had little effect on grating acuity.
(20) Methods are described for testing hypotheses on mean dioptric power and on variance-covariance of dioptric power for one and more than one population.
Refraction
Definition:
(n.) The act of refracting, or the state of being refracted.
(n.) The change in the direction of ray of light, heat, or the like, when it enters obliquely a medium of a different density from that through which it has previously moved.
(n.) The change in the direction of a ray of light, and, consequently, in the apparent position of a heavenly body from which it emanates, arising from its passage through the earth's atmosphere; -- hence distinguished as atmospheric refraction, or astronomical refraction.
(n.) The correction which is to be deducted from the apparent altitude of a heavenly body on account of atmospheric refraction, in order to obtain the true altitude.
Example Sentences:
(1) In the group of high myopia (over 20 D), the mean correction was 13.4 D. In the group with refraction between 0 and 6 D, 88% of the eyes treated had attained a correction between -1 and +1 D 3 months postoperatively.
(2) The molar refractivity has been shown to be a superior parameter for the description of the activity of sulphonamides than the sum of electronegativities of atoms making up a heterocyclic substituent in the sulphonamide molecule and molecular weight of the substituent.
(3) A new approach is presented to the refractive procedure by adding observation, both surreptitious and direct, as an adjunct, an aid and a supplement to differential diagnosis in a refractive examination and in visual analysis.
(4) Dioptric aniseikonia was calculated between 1 month and 24 months after surgery (with Gruber's and Huber's computer program) on the basis of most recently obtained values (bulb axis length, depth of the anterior chamber, lens thickness, necessary refraction), and compared with subjective measurements taken with the phase difference haploscope.
(5) These versions offer different advantages and are selected according to the particular field of application and the refraction of the surgeon.
(6) The refraction of his mild hyperopic eyes (+0,5 dpt) changed to -5,5 dpt and the intraocular pressure increased to 40 mm Hg in the right and 42 mm Hg in the left eye.
(7) These observations suggest that refractive anomalies such as anisometropia that limit high frequency spatial resolution and binocular integration can present a major obstacle to the postnatal development of binocular vision.
(8) A retrospective study was performed to evaluate the effect of recipient-donor trephine disparity on refractive error and corneal curvature post-suture removal in keratoconus.
(9) Scientists and clinicians concerned with underwater vision have not considered the relationship between chromatic aberration, water color, and the refractive state of the eye.
(10) As the refractive status changes a curve is traced out on the graph.
(11) The change in refractive astigmatism was as high as 1.50DC (diopter cylinder).
(12) There is a problem in this approach if the angle between the direction of tracked beam and the direction of tracking translation is not zero due to refraction or other effects.
(13) We find good agreement between the model calculations and the experimental results indicating that edge birefringence can be attributed to the change in polarization of light that is refracted and reflected by dielectric interfaces.
(14) The corneal sensibility was examined with the aesthesiometer of Draeger in 41 patients after refractive corneal surgery, 31 patients after radial keratotomy, 5 after epikeratophakia, 5 after excimer laser ablation.
(15) Extraordinarily wide angles were observed in all cases and myopia was a common refractive error.
(16) There was no connection between the cholesterol level, refraction or visual acuity.
(17) The refractive changes in 84 children (155 eyes) following horizontal strabismus surgery and in 97 children (181 eyes) without surgical intervention were studied.
(18) Refractive error and the ocular refractive components have heritabilities intermediate between zero and one, as complied from several studies, indicating familial resemblance, but also non-genetic variation.
(19) Approximately 75% of repeat autorefractor measurements were within 0.50 D of the initial readings, and about 75% of measurements were within 1.00 D of the manual refractions.
(20) The refractive index profile in the equatorial plane of bovine lenses from over a wide age range is presented.