The wearable optics unit resembles an eyeglasses frame that can be worn by itself or over the participant’s prescription eyeglasses. It contains miniature “eye cameras” that view each eye and a “scene camera” that views the scene in front of the participant, and a microphone.
The left and right bottom sections of the frame each include a panel containing a camera and a pair of LEDs. The panels rotate within an outer enclosure so that it is possible to adjust the camera vertical aiming direction with respect to the optics frame. Although these panels are usually best left in their standard position, it may be necessary to use this adjustment if facial structure makes the optics frames sit in an unusual position or angle on the face.
The frame comes with three nosepieces that can be interchanged to adjust the vertical position of the entire frame with respect to the face. To remove a nosepiece, simply pull the nosepiece horizontally away from frame. Attach a nosepiece by pressing the two pins on the nosepiece into the mating holes in the frame. The frame can also be worn with no nosepiece to position the frame at the lowest possible position on the face.
A microphone is located in the part of the frame that sits just above the participant’s eyebrows.
An optional visor attaches and detaches from the frame by mating small slots at the upper corners of the visor with small hooks on the frame.
The scene camera lens protrudes from the frame just above the nosepiece. Scene camera focus is adjusted by rotating the lens. An M2, hex head, nylon tip setscrew, located at the bottom of the lens assembly, controls the “tightness” of the focus adjustment, and should be tight enough to prevent unintentional rotation of the lens.
An HDMI type cable extends from the right temple clamp (piece that extends from the temple to the top of the ear). It connects to the frame with a micro HDMI connector in the temple clamp, but is intended to be disconnected only if it necessary to replace the cable. The other end of the cable has a standard “type-A-to-micro” HDMI connector and connects to the ETVision Controller.
The small Controller (slightly larger than a smart phone) easily fastens to an adjustable belt or can be held by the participant (or near the participant) in some other way. The Controller holds a micro SD card for video and audio data recording, and includes a rechargeable battery. It can also be powered directly from a DC power supply.