Optonet Vision Unit Documentation

Please note that this User Guide is being currently updated; new sections will be added shortly.

  1. QuickStart Guide (in 5 steps)
    1. Step 1. Choosing Hardware
    2. Step 2. Installation and Calibration
    3. Step 3. Menus
    4. Step 4. Control of Menus and Charts
    5. Step 5. Customise Sequences of Charts
    6. How to check if my charts are well calibrated?
  2. Home-based Vision Training (Orthoptics)
    1. Patient Selection
    2. Calendar
    3. Daily Exercise Program
    4. Parameters
    5. Comments
    6. Login Credentials for the patient
    7. Attaching documents
    8. Save Therapy
    9. Access as Patient
    10. Remote monitoring of patient progress
    11. Management of Patient’s Access
  3. Virtual Eye Clinic
  4. Visual Acuity
    1. logMAR VA
    2. Logarithmic Notation
    3. VA Rating (VAR) or VA Score (VAS)
    4. VA Tools Menu
      1. Selecting Rows and VA Values.
      2. Visual Acuity Range
      3. Bi-Chrome Function
      4. Isolated Optotypes (Rows, Columns and Letters)
      5. Contrast
      6. Randomizing the order of optotypes
      7. Vanishing Optotypes
      8. Intermediate Steps
      9. Tablet as a remote controller for VA
    5. VA Optotypes
      1. Sloan letters
      2. British Letters
      3. Numbers
      4. Landolt Optotype "C"
      5. E of Snellen
    6. References Visual Acuity
    7. Paediatric Visual Acuity
      1. Test of “Broken Glasses”
      2. Symmetrical Optotype
      3. References Paediatric Visual Acuity
    8. Automated Visual Acuity Testing
      1. ETDRS, Bailey-Lovie, Snellen E, Numbers and Landolt C
      2. Symmetrical Letter Chart
      3. Broken Glasses Chart
      4. References Automated VA Testing
      5. VA Testing Protocol > 8 years old (printable document)
      6. VA Testing Protocol ≤ 8 years old (printable document)
  5. Setup
    1. Colour Calibration

4.4.5.Contrast #

All VA optotypes are initially displayed at maximum contrast (100%). However, you can modify the contrast of the optotypes using either of two icons of the tools menu or using a keyboard shortcut (combine “Control” with right → or left ← arrows). Either method allows you to increase or decrease the contrast of the optotypes. The values of Contrast Sensitivity (CS) are displayed in the lower left corner of the screen. You can display the units of the measure by passing the mouse over the number. The default is a log unit, but you can change to a percentage value by clicking the number, or by typing “Q”. Clicking or typing “Q” a second time returns to the default (log) unit.

 

 

The contrast varies from 100% (0.0 log) to 0.5% (2.30 log), in steps of 0.15 log.

« Isolated Optotypes (Rows, Columns and Letters)Randomizing the order of optotypes »
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