Thomson Acuity Master

Visual Acuity measurement and analysis made simple

Why the Thomson Acuity Master?

Acuity Master is designed for hospital eye departments and clinics where the principal requirement is the accurate and efficient measurement of visual acuity.

The software requires a PC with dual screens - one to display the control panel and the other to display the test chart.

A nurse or technician uses the control screen to select the required test and enter the patients' responses.  Letter size is varied according to a staircase algorithm to establish a reliable and repatable acuity measurement.

LogMAR scores are calculated automatically and results are stored in a database or may be printed on a label to add to paper-based records.


Acuity Master Software

£32 +VAT / month

  • Includes all upgrades, updates and support. Minimum term 6 months.

For multiple licences, please call for a quote.  Special rates are available for Hospitals, Universities and Research Institutions.

A more detailed look at the Acuity Master

The patient is seated at between 2.5 and 6 metres (customisable) from a  monitor. This monitor may be connected wirelessly to the computer or laptop.


The nurse or technician operates the program from an intuitive control interface of a second screen next to the patient.

The operator enters the patient's details into the database.


Selects the test conditions: right or left eye, Unaided, Aided, Pinhole, Low contrast or Binocular and selects the name of tester.


A range of optotypes are available for children and those who may be unable to name letters. Optotypes include: Sloan (ETDRS), British, Tumbing E, Landolt C and Kay pictures (optional).

The operator then simply starts the test. The patient sees the chart with a red line next to the row they are to read. The operator can select a single row of letters with crowding bars if they prefer.


The operator then simply records how many letters on the row that are read correctly. The score appears automatically


Or if you prefer ... the computer can do the hard work for you. Select Auto and the screen changes to a single column of letters. The operator simply records if the letter can be read by the patient. If it can, the letter size decreases. If it can't, the letter size increases. This gets you to approximately the correct acuity within a few seconds.

At this point, a single row of letters with crowding bars is displayed. The operator simply records the number of letters on this row which can be read. If more than one letter on the row is read, the letter size is reduced by 0.1 LogMAR and the process is repeated until no letters can be read.


And that's it! The LogMAR score is automatically recorded and you can move on to the other eye or another condition.

Having completed the tests, click on Save and the results are added to the database. The software automatically generates a timeline of results so that you can see how the patient's visual acuity has changed over time. The report may be printed or saved as a pdf to be attached to the patient's records.


If you use paper-based records, a label of the test results can be printed and attached to the record.

What about low vision patients? For patients with very poor vision, it may not be possible to display five large letters on the screen. Acuity Master offers two options:

  1. If less than five letters can be displayed on the screen, the patient is moved to a closer viewing distance (e.g. 1 metre).  The software automatically adjusts for this change in viewing distance.
  2. If you prefer not to move the patient, partial rows of letters are displayed (as shown).  The row is then displayed in two or more presentations but is otherwise scored in exactly the same way.

In addition to the visual acuity tests, Acuity Master includes a low contrast visual acuity test ...

... a number plate test using exact number plate fonts and spacing - scaled for the current viewing distance ...


... and a huge range of photos and diagrams to entertain and educate. The slide show option automatically rotates through the images and if you don't like the 500 or so images we provide, you can add your own. You can also play videos from within the system!

We recognise that each eye department tends to have its own preferred protocol so Acuity Master is highly configurable. You can select the exact letters you want to use on your charts and set different letter sets for different conditions. You can use the system with or without the database function, set viewing distances, screen configurations and virtually everything else.


Testimonials ...

This system has greatly improved the accuracy and efficiency of visual acuity measurement in our eye department.

Acuity master is simplicity itself to use. Our nurses were entirely confident using it by the end of the training session.

Acuity Master has not only made visual acuity testing quicker, it has greatly improved the accuracy of measurements (and reduce the number of scoring errors!)

We highly recommend this software.

We have been using Thomson test Charts in our department for years and love it. This latest addition to their portfolio is brilliant for our Lucentis clinic.

Key features

  • Automated measurement of visual acuity
  • Quick and accurate
  • Very simple to use
  • Powerful database for saving results
  • API to link with other databases and record systems
  • Variable viewing distance
  • LogMAR range (-0.4 to 1.6)
  • Low Contrast Acuity Test
  • Number plate test for UK driving standard test
  • Slide show with images and videos
  • Graphical reports
  • Label printer option