AT20R Specifications

Click to enlarge

Letter Sizes

• LogMAR steps 6/3.0 - 6/120

Visual Acuity Selection

• US 20/12 - 20/400
• UK 6/4 - 6/120
• EU 1.5/0.05
• Snellen Letters
• Sloan Letters
• Illiterate "E"
• Landolt "C"
• AHOTX
• ETDRS
• Numbers
• "LEA" Children's charts

Acuity Chart Display Options

• Multiple Line Decreasing
• Multiple Line Equal
• Single Letter
• Single Letter with interaction bars
• Single Column Decreasing
• Single Column Equal
• Single Line
• "Staircasing" measurement of visual acuity

Cross Cylinder Targets

• Dual rings
• Hexagonal pattern
• Crossed Lines
• Adjustable sizes

Duochrome Screen

• Dual Rings
• UH Letters
• Adjustable sizes

Astigmatism measurement 

• Fan: 180°; 15° steps
• "V": 2.5° or 5° steps
• "L": located at "V" angle

Binocular Vision Tests

• Worth 4 dot
• Horizontal fixation disparity
• Vertical fixation disparity

Fixation Targets

• White dot
• Changing coloured dot
• 3D Animated children's targets
• User specified video/images

Patient Information Display

• Various images and diagrams of the eye and occular conditions
• User specified video/images

Contrast Sensitivity

• Staircase test to determine contrast threshold
• Adjustable contrast available for all acuity charts

Gratings Display

• Square/sine wave gratings
• 1.5 cycles/degree to 60 cycles/degree
• 3 orientations

Other Facilities

• Various images and diagrams of the eye and ocular conditions
• Contrast sensitivity measurement using "staircasing" technique to determine contrast threshold
• Normal/reverse image for direct mirror viewing
• Random display option for acuity charts
• Scaling for actual viewing distance