Closed caption display devices were shown at ShowEast by USL and Doremi. While the end displays are somewhat similar in appearance, the technology behind each is very different.
Both devices sit on goosenecks that mount in the cup holder. Both use battery-driven electronic displays to display the caption text. The USL device uses a special lens to limit the spread of light, while Doremi relies on louvers in front of the display. USL uses infrared light to transmit caption data to the display. The same infrared transmitter can also send assistive listening audio to headsets. (The user can use the closed caption display independently of the headsets, and vice versa.) Infrared has the desirable feature that it won’t leak into a neighboring auditorium. Doremi uses IEEE 802.15.4, a technology similar to Bluetooth, also known as ZigBeeTM. Presumably some configuration is needed at the display to prevent receipt of the wrong wireless signal. The Doremi solution does not support assistive listening features.
Under the hood, USL uses the SMPTE Closed Caption Protocol from server to transmitting device. The advantage for users with this protocol is that other manufacturers of closed caption displays can utilize the same royalty-free output. Doremi uses a proprietary technique where the ZigBee transmitter plugs directly into the server. Doremi is attempting to license its technology to other server companies.
USL did not have its closed caption glasses on display. Frames and lenses for the final unit were not ready in time for the trade show. The glasses will operate from the same infrared signal used by its cup holder-mounted display.
The great irony is that Doremi is attempting to go down the licensing route, following in the footsteps of DTS and WGBH with the Rear Window system. The purpose of the SMPTE effort for the open SMPTE 430-10/11 closed caption protocol was to eliminate licensing. Only exhibitors can decide.
