Turning Point Qs Flashcards
Tear film stability is primarily referring to
Evaporation rate
Irregularities in the tear film over a period of time improves the retinal image quality
No
If the central corneal thickness (CCT) gets thinner than normal (0.5mm) leads to _____ of IOP
Underestimated
Refraction in human eye due to
Anterior + posterior+ GRIN lens
Calculate the AA of an eye with a far point of 1m and a near point of 25cm
1/1=1D
1/.25m=4D
4-1=3D
3D
Anterior corneal asphericity Q value of human cornea is ______
Negative
What should be the Q value required to eliminate corneal spherical aberration
-0.528
Radius of curvature along tangential meridian is steeper than RoC along Sagittal meridian,
True
Spherical aberration will increase as anterior corneal curvature becomes
Steeper
At accommodative state, the refraction of the crystalline lens is
31.85D
Crystalline lens axial thickness increases all through life at a rate of _____ per year
13 microns
The line connecting the foveola and the fixation point passing through the nodal points is
Visual axis
The line connecting the foveola and the fixation point passing though the nodal point is
Line of sight
The position at which the line of sight intercepts the cornea is called
Corneal sighting center
Angle between the pupillary axis and LoS is _______
Angle lambda
Scholars use ________ model eye to store and retrieve knowledge
Both utilitarian tool and encyclopedia
Who was the first to realize the existence of the inverted retinal image, and understood how to correct refractive errors
Kepler
Scheiner invented the first ever optometer to measure the _____________ in the human eye
Refractive error
What is the optical power of the tear film
48D
Tear film is composed of three layers, name the top most layer
Oily
Tear film stability is primarily referring to
Evaporation rate
Irregularities in the tear film over a period of time improves the retinal image quality
False
Dry eye patients generate higher order aberrations like spherical aberration and _______ about 2.5 times more than the healthy eyes
Coma
Cornea has ______ of the total power of the eye
2/3
Anterior corneal asphericity Q value of human cornea is _____
Negative
What should be the Q value required to eliminate corneal spherical aberration
-0.528
Spherical aberration will increase as anterior corneal curvature becomes
Steeper
If the central corneal thickness gets thicker than normal (0.5mm) leads to _______ of IOP
Overestimation
Which part of the GRIN crystalline lens of the human eye has the lowest refractive index
EQUATOR
Refraction in human eye due to
Anterior + posterior + GRIN lens
At accommodative state, the refraction of the crystalline lens is
31.85D
Calculate the AA of an eye with a far point of 1m and a near point of 25cm
3D
In a trifocals IOL, the potential intermediate vision helps you to ______ better
Watch TV
Extended range of vision IOLs claims to provide good continuous vision and reduce ______
Glare and halo
What is the job description of the Iris
- Stop undesirable light
- Regulates retinal illuminations
- controls DoF
- controls retinal blur
- help design optical systems
Exit pupil is the image of the aperture stop formed on the image space
True
Entrance pupil is an erect, _______ image formed in front of the actual pupil
Virtual
DoF for the human eye is between 0.5 and ____D
1D
The line connecting the foveola and the fixation point passing through the nodal points is
Visual axis
The position wt which the keratometric axis intercepts the cornea is called
Vertex normal
Angle between the pupillary axis and LoS is
Angle lambda
What is the disadvantage of using working model (toy train) for solving problems of vision science
Oversimplified
Who was the first to develop a average schematic model eye
Young
Applying the simplification of hte model eye concept, how many surfaces does the Bennett rabbetts model have
3
Which of the 4 purkinji images forms image real and inverted
Purkinji IV
Some corneal typographers and keratometric work based on the principle of
Purkinji I
Consider the light source is at infinity ad a femal anterior cornea RoC is 7.93mm. Determine the location of the purkinji image I by treating anterior corneal surface as a mirror
3.965
How can we best express the separation of two stars
Arcsec
In a corrected eye, what causes blur
Diffraction and aberrations
A more confined PSF is achieved with
A larger pupil
Which of the following is a diffraction limited PSF
Pointy one
Better vision is achieved with
A more confined PSF
Which of the following can be parameterized
Wavelength and diameter of pupil
