Biomedical Engineering Reference
In-Depth Information
CHAPTER 13
Retinal Image Size
1
1
⎞
⎠
⎛
⎞
⎛
⎝
1.
M
spect
=
⎟
t
⎟
1
−
dF
v
⎝
⎞
⎠
1
−
F
1
⎝
⎠
1
1
⎛
⎝
⎞
⎠
⎛
⎞
M
spect
=
⎟
⎟
1
−
(0.012 m)(
−
6.50 D)
⎡
⎥
0.002 m
1.586
⎤
⎥
⎝
⎠
1
−
(
+
3.00 D)
⎝
⎠
M
spect
=
(0.928)(1.00)
M
spect
=
0.928
×
2. (a)
Right lens
:
1
1
⎛
⎝
⎞
⎠
⎛
⎞
M
spect
=
⎟
t
⎟
1
−
dF
v
⎛
⎞
⎠
1
−
F
1
⎝
⎝
⎠
1
1
⎛
⎝
6.00 D)
⎛
⎝
⎞
⎠
⎞
M
spect
=
⎟
⎟
1
−
(0.014 m)(
−
⎡
⎥
0.002 m
1.498
⎤
⎥
⎝
⎠
1
−
(
+
2.00 D)
⎠
M
spect
=
(0.923)(1.00)
M
spect
=
0.923
×
Left lens
:
1
1
⎞
⎠
⎛
⎞
⎛
⎝
M
spect
=
⎟
t
⎟
1
−
dF
v
⎝
⎠
1
−
F
1
⎝
⎠
1
1
⎛
⎝
⎞
⎠
⎛
⎞
M
spect
=
⎟
⎟
1
−
(0.014 m)(
−
3.00 D)
⎡
⎥
0.002 m
1.498
⎤
⎥
⎝
⎠
1
−
(
+
2.00 D)
⎝
⎠
M
spect
=
(0.960)(1.00)
M
spect
=
0.960
×
(b) If the shape factor of the right lens were increased to 1.04
×
(i.e.,
0.960/0.923
), the images in both eyes would be the same size.
We calculate the front surface power of the 4.00 mm thick right lens as
follows:
=
1.04
×
