Midterm Eye recording Techniques

Question 1

What are the 3 main methods that you can transform eye movements into electrical signals to be analyzed by computers?

Answer 1

1. Electro-oculography (EOG/ENG)
2. Infrared Video - Oculography (VOG/VNG)
3. Scleral Search coils

Question 2

what are CRP

Answer 2

Bioelectrical signal used for recording EOG/ENG

Question 3

How can EOG/ENG track eyes?

Answer 3

Via CRP
- the eyeball cornea + polarized & Retina - polarized
- creats a steady electrical potential field that may be detected with the eyes in total darkness and or with eyes closed

Question 4

For EOG/ENG impedance needs to be

Answer 4

impedance need to be <10,000 ohms; inter-electrode impedance <3,000 ohms

Question 5

• make use of pupil localization technology & reflective nature of corneal surface to calculate pupil position & angle of gaze
• Goggles contain infrared diodes to illuminate the eyes and reflects the image of the eyes into a pair of camera for recording

Answer 5

Infrared Video - Oculography

Question 6

explain how Infrared Video Oculography works

Answer 6

• make use of pupil localization technology & reflective nature of corneal surface to calculate pupil position & angle of gaze
• Goggles contain infrared diodes to illuminate the eyes and reflects the image of the eyes into a pair of camera for recording
• infrared light is not visable to human only to system

Question 7

• Coils are embedded into a tighly - fitting contact lens
• lens is surgically implanted
• alternating magnetic fields are generated around eye though electromagnetic induction

Answer 7

Scleral Search Coil