VSP
1. Pigment of macula Lutein
lutea Zeaxanthin
Meso-zeaxanthin
2. Rod count 120 million
3. Cone count 6 million
4. Rod peak density 20 deg (~6 mm) from fovea
5. Cone peak density 0 deg.
Highest at the fovea
6. Rod time response Slow
7. Cone time re- Fast
sponse
8. Rod directionality No
Sensitive to scattered light
9. Cone directionality Yes
Sensitive to direct light
10. Rod Photopigment Rhodopsin
11. Cone photopig- Chlorolabe
ment Cyanolabe
Erythrolabe
12. Rod light sensitivi- High
ty
13. Cone light sensitiv- Low
ity
14. Cone temporal res- High
olution ~60Hz
15. Low
, VSP
Rod spatial sensi-
tivity
16. Cone spatial sensi- High
tivity
17. Rod adaptation 30-40 mins
18. Cone adaptation 5-8 mins
19. Rhodopsin max ab- 507 nm
sorption
20. Cyanolabe max ab- 426 nm
sorption
21. Chlorolabe max ab- 530 nm
sorption
22. Erythrolabe max 560 nm
adaptation
23. Rhodopsin mole- 10^7
cules in one rod
24. Rhodopsin mole- 10^15
cules in whole reti-
na
25. Time for Rods to 40 mins
absorb photon
26. CHAPTER 5 CHAPTER 5
27. equation of energy E= hc/»
in a photon
28. What did the Hecht, minimum light energy (minimum number of photons)
Shlaer & Pirenne required to result in the perception of light
, VSP
experiment try to
determing?
29. Conditions for scotopic conditions (dark adapted subject, 40 mins)
Hecht, Shlaer &
Pirenne experi- 20 deg. retinal eccentricity
ment
stimulus size of 10 min of arc (<50 min of arc)
1 ms stimulus duration (<100 ms)
stimulus 510 nm wavelength
fixation point of ~650nm to be invisible to rods and not
to disturb dark adaptation
30. what happens to increases due to an increase in the receptive field of
the critical diam- ganglion cells
eter of a stimu-
lus under scotopic
conditions as reti-
nal eccentricity in-
creases?
31. what happens complete spatial summation
when the stimulus
size is smaller than
that of the critical
diameter?
(scotopic vs pho-
topic?)
32. critical duration ~100 ms
of stimulus un-
der scotopic condi-
tions
33. what happens complete temporal summation
when a stimulus
duration is shorter
, VSP
than the critical du-
ration?
(scotopic v pho-
topic?)
34. peak scotopic 505 nm
spectral sensitivity
35. dispersion seperating the wavelengths of a light source by using a
refractive index
36. T/F true
the refractive in-
dex of a material this is the source of chromatic aberrations
is wavelength-de-
pendent
37. neutral density fil- equally reduces the intensity of all the wavelengths in
ter function the spectrum
38. optical density of OD = -log10 (transmitted light intensity/incident light
neutral density fil- intensity)
ter equation
39. transmitted light I = (10^(-OD)) * (Io)
intensity equation
*neutral density fil-
ter
40. What percent of formula:
incident light is (10^-OD)*100
transmitted by a
neutral density fil- Ans: 1%
ter with OD = 2
41. T/F True
according to HSP
experiment, the
1. Pigment of macula Lutein
lutea Zeaxanthin
Meso-zeaxanthin
2. Rod count 120 million
3. Cone count 6 million
4. Rod peak density 20 deg (~6 mm) from fovea
5. Cone peak density 0 deg.
Highest at the fovea
6. Rod time response Slow
7. Cone time re- Fast
sponse
8. Rod directionality No
Sensitive to scattered light
9. Cone directionality Yes
Sensitive to direct light
10. Rod Photopigment Rhodopsin
11. Cone photopig- Chlorolabe
ment Cyanolabe
Erythrolabe
12. Rod light sensitivi- High
ty
13. Cone light sensitiv- Low
ity
14. Cone temporal res- High
olution ~60Hz
15. Low
, VSP
Rod spatial sensi-
tivity
16. Cone spatial sensi- High
tivity
17. Rod adaptation 30-40 mins
18. Cone adaptation 5-8 mins
19. Rhodopsin max ab- 507 nm
sorption
20. Cyanolabe max ab- 426 nm
sorption
21. Chlorolabe max ab- 530 nm
sorption
22. Erythrolabe max 560 nm
adaptation
23. Rhodopsin mole- 10^7
cules in one rod
24. Rhodopsin mole- 10^15
cules in whole reti-
na
25. Time for Rods to 40 mins
absorb photon
26. CHAPTER 5 CHAPTER 5
27. equation of energy E= hc/»
in a photon
28. What did the Hecht, minimum light energy (minimum number of photons)
Shlaer & Pirenne required to result in the perception of light
, VSP
experiment try to
determing?
29. Conditions for scotopic conditions (dark adapted subject, 40 mins)
Hecht, Shlaer &
Pirenne experi- 20 deg. retinal eccentricity
ment
stimulus size of 10 min of arc (<50 min of arc)
1 ms stimulus duration (<100 ms)
stimulus 510 nm wavelength
fixation point of ~650nm to be invisible to rods and not
to disturb dark adaptation
30. what happens to increases due to an increase in the receptive field of
the critical diam- ganglion cells
eter of a stimu-
lus under scotopic
conditions as reti-
nal eccentricity in-
creases?
31. what happens complete spatial summation
when the stimulus
size is smaller than
that of the critical
diameter?
(scotopic vs pho-
topic?)
32. critical duration ~100 ms
of stimulus un-
der scotopic condi-
tions
33. what happens complete temporal summation
when a stimulus
duration is shorter
, VSP
than the critical du-
ration?
(scotopic v pho-
topic?)
34. peak scotopic 505 nm
spectral sensitivity
35. dispersion seperating the wavelengths of a light source by using a
refractive index
36. T/F true
the refractive in-
dex of a material this is the source of chromatic aberrations
is wavelength-de-
pendent
37. neutral density fil- equally reduces the intensity of all the wavelengths in
ter function the spectrum
38. optical density of OD = -log10 (transmitted light intensity/incident light
neutral density fil- intensity)
ter equation
39. transmitted light I = (10^(-OD)) * (Io)
intensity equation
*neutral density fil-
ter
40. What percent of formula:
incident light is (10^-OD)*100
transmitted by a
neutral density fil- Ans: 1%
ter with OD = 2
41. T/F True
according to HSP
experiment, the
