Dr.Shivalinge Gowda KP Professor and HOD Dept of Pharmacology PES College of Pharmacy Bengaluru-560050

1. Expt No-7 HAP-I (P) Batch-A Date 21-9-2017 Prof. Dr.KPS Gowda PESCP Page 1
Expt No- 7 To demonstrate the visual acuity I B.Ph- Batch A Date- 21-9-2017
Distant visual acuity
a. To examine the visual acuity for distant vision using Snellen chart.
The visual acuity test is used to determine the smallest letters that can be read on a standardized
chart (Snellen chart) or a card held 20 feet (6 meters) away. Visual acuity (VA) commonly refers
to the clarity of vision. A Snellen chart is an eye chart that can be used to measure visual acuity.
Each eye tested separately. The Snellen chart consists of varying sizes constructed so that the top
letter is visible to the normal eye at 20 feet (60m) and the subsequent lines at 36, 24, 18, 12, 9, 6
and 5m respectively. Visual acuity (V) is recorded according to the ration, d/D where d is the
distance at which the letters are read, and D is the distance at which they should be normally
read. The subject is made to sit at a distance of 6m from the test types (d-=6m). The subject reads
down the chart as far as he or she can.
If a subject can read only the top line, V= 6/60
Next line, V= 6/36 and so on.
If V is less than 6/60, then the subject is moved towards the test types, until they can read the top
letter. If the top letter is read at 2m distance, then V= 2/60.
Visual acuities of less than 1/60 are recorded as counting fingers (CF)
Hand movements (HM)
Perception of light (PL)
No perception of light (no PL)
Report- The distant vision acuity of my eyes was found to be
Visual acuity for near vision
b. To examine the vision acuity for near vision your own using Grafco Jaeger chart-
Theory- The Jaeger chart is an eye chart used in testing near vision acuity. Near visual acuity
measurements are an important part of general vision assessment.
The Grafco Jaeger Eye Chart is used to measure near visual acuity. The chart has print samples
of different sizes that are used to determine one's near vision. The paragraph with the smallest
print is No. 1. The paragraph with the next larger print is No. 2, and so on, to the largest print
(paragraph No. 11). The person with lesser visual acuity not able to read smaller prints present in

2. Expt No-7 HAP-I (P) Batch-A Date 21-9-2017 Prof. Dr.KPS Gowda PESCP Page 2
the Jaeger chart. Persons with normal vision should be able to read the smallest print in good
lighting, at a comfortable reading distance 35 cm/ 14 “.
Procedure-
1. Hold the test card 14 inches from the eyes. Use a tape measure to verify this distance.
2. The card should be illuminated with lighting typical of that used for comfortable reading.
3. Testing usually is performed with both eyes open; but if a significant difference between the
two eyes is suspected, cover one eye and test each eye separately.
4. Go to the smallest block of text that can be read.
5. Continue reading successively smaller blocks of print until you reach a size that is not legible.
6. Record the “J” value of the smallest block of text that can be read (example: “J1”).
Report- The vision acuity for the near vision of my eyes was found to be
Colour Vision
c. To examine the colour vision of your own using Ishihara Chart.
The Ishihara test is a colour perception test for red-green colour deficiencies. The test consists of
a number of coloured plates, called Ishihara plates, each of which contains a circle of dots
appearing randomized in colour and size. Within the pattern are dots which form a number or
shape clearly visible to those with normal colour vision, and visible, or difficult to see, to those
with a red-green colour vision defect. The full test consists of 38 plates, but the existence of a
severe deficiency is usually apparent after only a few plates. There is also an Ishihara test
consisting 10, 14 or 24 test plates. For each plate, test the result using key provided in the
Ishihara chart.
The current passing score is 12 correct of 14 red/green test plates (not including the
demonstration plates). The scores below twelve indicate colour vision deficiency, and twelve or
more correct indicate normal colour vision.
Report- The colour vision score of my eyes was found to be . Hence my eyes found to be
normal/abnormal with respect to the colour vision.