The Thomson Test Chart includes 15 different optotypes, each of which may be displayed in LogMAR, Snellen or Single letter format.

Name

Description


Sloan letters

Standard optotype constructed on a 5 x 5 matrix


British letters

Standard optotype complying with BS4724 constructed on a 5 x 4 matrix


Tumbling Es

“E”s of different orientations. Useful for assessing pre-literate children and adults who are not familiar with the English alphabet.


Landolt Cs

The optotype that is generally considered to be the most reliable for assessing visual acuity. Still used as the Gold-Standard for evaluating new optotypes.


Auckland Optotyes

Selection of picture optotypes designed and developed the University of Auckland for assessing the vision of pre-literate children.


New Kay pictures

Selection of picture optotypes designed and developed by Hazel Kay. Popular for assessing the vision of pre-literate children.


Old Kay pictures

Older selection of picture optotypes designed and developed by Hazel Kay. Popular for assessing the vision of pre-literate children.


Sheridan-Gardner letters

Symmetrical letters which may be used with or without a mirror and matched to a standard Sheridan-Gardner matching chart


Lower case letters

Children often learn their lower case letters before the capital letters that are conventionally used on test charts. The font is designed to resemble the style of handwriting. This type of chart is useful for assessing the vision of children between 4 and 6 years of age.


Makaton symbols

Selected icons from the Makaton signing system for assessing the vision of individuals with profound learning difficulties.


Numbers

Selected numbers. Useful for assessing pre-literate children and adults who are not familiar with the English alphabet.


Gujarati

A selection of Gujarati characters stylised to give an approximate measure of visual acuity.


Punjabi

A selection of Punjabi characters stylised to give an approximate measure of visual acuity.


Arabic

A selection of Arabic characters stylised to give an approximate measure of visual acuity.


Hebrew

A selection of Hebrew characters stylised to give an approximate measure of visual acuity.

Mouse

Select the required optotype from the pull-down list in the toolbar 




Keyboard

1-8 Selects optotypes 1 to 8 as shown above.


Remote

Display mode keys select optotypes 1-8