Novel Wearable Optical Display

Trulife Optics together with the UK’s National Physics Laboratory has demonstrated a new type of transparent head-up display device.

(Source: TrueLife)

(Source: Truelife Optics)

According to Simon Hall, lead scientist of Adaptive Optics at the NPL the new technology is unlike existing solutions: “Google’s solution is effectively a prism; it’s like a half-silvered mirror that you’re looking into and the Epson Moverio uses an embedded, slightly different refractive index component in a very thick lens which is reflecting light travelling through the rather thick waveguide”.

This new component is set to transform the development of wearable augmented reality and head-up display devices. Jonathan Lewis, CEO at Trulife optics commented that, “The development of wearable augmented reality devices has been curtailed by the lack of an optical component that allows for the overlay of high-definition, full colour images. But with the launch of our optic, we are providing that missing piece in the augmented reality jigsaw.”

Light carrying the image information is transmitted into the first hologram and then turned through 90° through the length of the optical waveguide using total internal reflection before hitting the second hologram. Here it is turned a further 90° then projected into the human eye. This allows for overlaid transparent images to be projected from the centre of the optic in perfect focus. The image is transparent, enabling the overlay of information on whatever subject is being viewed. The optic itself is lightweight, less than 2mm thick, and can be easily mass-produced for consumer and industrial applications.

The device is available now and costs approximately $514 (£300) plus VAT per unit for developers creating prototype devices. The cost of the optic for devices to be made in commercial volumes will depend on the final application and device to be produced.

[via Elektor — Source: Trulife optics]

Two-Channel CW Laser Diode Driver with an MCU Interface

The iC-HT laser diode driver enables microcontroller-based activation of laser diodes in Continuous Wave mode. With this device, laser diodes can be driven by the optical output power (using APC), the laser diode current (using ACC), or a full controller-based power control unit.

The maximum laser diode current per channel is 750 mA. Both channels can be switched in parallel for high laser diode currents of up to 1.5 A. A current limit can also be configured for each channel.

Internal operating points and voltages can be output through ADCs. The integrated temperature sensor enables the system temperature to be monitored and can also be used to analyze control circuit feedback. Logarithmic DACs enable optimum power regulation across a large dynamic range. Therefore, a variety of laser diodes can be used.

The relevant configuration is stored in two equivalent memory areas. Internal current limits, a supply-voltage monitor, channel-specific interrupt-switching inputs, and a watchdog safeguard the laser diodes’ operation through iC-HT.

The device can be also operated by pin configuration in place of the SPI or I2C interface, where external resistors define the APC performance targets. An external supply voltage can be controlled through current output device configuration overlay (DCO) to reduce the system power dissipation (e.g., in battery-operated devices or systems).

The iC-HT operates on 2.8 to 8 V and can drive both blue and green laser diodes. The diode driver has a –40°C-to-125°C operating temperature range and is housed in a 5-mm × 5-mm, 28-pin QFN package.

The iC-HT costs $13.20 in 1,000-unit quantities.

iC-Haus GmbH
www.ichaus.com