The subject of the public contract is the delivery of one piece of Snell's digital
optotype.
The procedure followed for applying the P&R test consisted of all the participants in the study reading (in monocular and binocular vision) the letters located on the
optotype, beginning with the top row and continuing until two of the three letters in the same group were read incorrectly.
Images included Lea symbols (circle, square, house, or apple; Figure 1(a)), posted on a 15-line vision
optotype chart [24].
Enrolled subjects underwent unaided visual acuity testing for distant vision using snellen's chart and near vision
Optotype chart.
3) It is, therefore, important to perform an
optotype test with crowding, when a child is old enough.
1997, for basal ganglion disorders; Ek, Fellenius, & Jacobson, 2003, and Jacobson & Dutton, 2000, for improved
optotype acuity for PVL).
Lot 1: Angiograph-October- Lot 2: corneal topographers- Lot 3: Slit Lamp with a picture Digestive- Lot 4: Slit Lamps (3)- Lot 5: Screens
optotype (10)
For letter charts, factors such as the
optotype design, spacing and interaction effects from adjacent visual contours (crowding) can all affect visual acuity measurement.
But these methods of assessing acuity are not as good at detecting strabismic amblyopia as crowded
optotype tests and, as soon as possible, this type of test should be used.
The letters can be interchanged for different languages, while it also allows the user to change the
optotypes to the universal language of numbers.
A functional scale seems essential for preschool children with visual impairments whose visual acuity cannot be recorded using
optotypes.
Children less than 2 years with good co-operation and response Lea paddles, 2-4 years Lea symbols or single
optotypes such as Landolt C or HOTV (Simson 1983) was used and above 5 years Snellen's chart was used.
