The slope of the linear regression fit using stimuli and responses at each dioptric
level provided the closed-loop accommodative gain value .
Table 1 A review of myopia control data from 2011 (26) Method Cochrane review conclusion (2011) Spectacles Under-correction versus full * Limited evidence favouring correction full-correction compared with under-correction Progressive addition lenses * Clinically insignificant benefit of versus single vision using PALs * Dioptric
refractive error changes are not supported by changes in axial length and corneal curvature Bifocals versus single vision * Limited and inconsistent evidence Contact lenses Bifocal versus single vision * Although a study has shown soft bifocal contact lenses to help reduce myopia progression, the study was described in the Cochrane review as being at 'high risk of bias' Rigid gas permeable lenses * Conflicting evidence.
23-25) Some recent AIOL designs incorporate additional features to aid near vision, for example, the Crystalens AO features aspheric optic surfaces with zero spherical aberration and is also designed to arch and steepen with accommodative effort to increase the eye's dioptric
Additional camera features include shutter speeds from 8 seconds to 1/1000 second; an iris diaphragm; built-in flash with five control modes; an eye-level electronic viewfinder with dioptric
correction; a wireless remote controller; and a high-capacity lithium-ion battery that can be recharged in the camera.
2D, inferior-superior dioptric
asymmetry (I-S value) >1.
5 3x zoom lens; 12 EOS System-based picture-taking modes; a wide exposure sensitivity range (equivalent to ISO 50-400); shutter speeds from 8 seconds to 1/1000 second; an iris diaphragm; built-in flash with five control modes; compatibility with Canon EX-series Speedlites; an optical viewfinder with dioptric
correction; a wireless remote controller; and a high-capacity lithium-ion battery power that can be recharged in the camera.
Magnification of such systems approximates to the dioptric
ratio of the eye piece lens to the objective lens.
corrector for viewfinder sharpness
In addition, its built-in light-guide flash, high-eyepoint viewfinder with built-in dioptric
adjustment and exclusive Best Shot dial make operation of the camera simple and stress-free.
It is important to make the distinction between accommodation, which is due to a dioptric
change with near vision and pseudo-accommodation which is due to increased depth of focus.
Correction - Dioptric
correction of -2 to +1 diopters
In addition, the Elan 7/7E includes a 7-point wide-area autofocusing system based on a Canon-developed CMOS sensor; a high-speed, 4 frames per second film advance and 1/4000 top shutter speed; 11 shooting modes; 13 Custom Functions; 35-zone evaluative metering; E-TTL flash control; built-in dioptric
adjustment; improved Whisper Drive; and a dedicated depth-of-field preview button.