A system (300) of personal computer comprising: a screen (310) display; a device (320) imaging, which comprises one or more chambers and which is adapted to provide data eye tracking by imaging at least one eye of an observer of the display screen; and means (330) for accepting input data from control eye tracking and other input data, wherein: the imaging device can switch between at least an active mode, an idle mode and ready; the switching time of the idle mode to the active mode is longer than the switching time of standby mode to active mode; the imaging device is configured to use the active ocular light in the active mode, which allows tracking of a corneal reflection; and wherein the imaging device is set in the ready mode, to reduce illumination intensity from the value that is in the active mode; and because the data eye tracking device that imaging is configured to provide the ready mode include eye position, but the orientation of the eyes.

Conventional dispersion compensation requires erbium-doped fiber amplifiers with high pump power to compensate for excess losses introduced by the dispersion-compensating fiber. We report and demonstrate an optimized single-pump amplifier configuration with a pump power penalty of less than 5% when integrated with a fiber Bragg grating dispersion compensator. The system is capable of compensating 100 km of G.652 single-mode fiber.

Conventional dispersion compensation requires EDFAs with high pump power to compensate for excess losses. With a new integrated dispersion compensator and amplifier design, we have shown a pump power penalty of less than 5% capable of compensating 100km G.652 fiber.

The laser diode technology, underpinning applications such as data storage, industrial lasers and optical telecommunications, still suffers from reliability and longevity limitations, especially in high power applications. A main problem for these lasers arises from facet oxidation, leading to increased absorption, power degradation and COMD device failure. Typically, high power devices initially show a low linear degradation and after some 100 hours, the degradation accelerates in a nonlinear fashion, indicating a degradation runaway condition. This article reports performance and reliability improvements that are based on a process which atomically seals surfaces and eliminates oxidation by forming stable nitrides on laser facets. The dangling bond terminating technology suppresses accelerated degradation associated with optical density and heat at laser facets. The dangling bond termination is demonstrated by improved COMD, decreased degradation at CW operation and a constant linear degradation rate at different QW temperature conditions (nonlinear degradation indicates advancement in the oxidation/optical absorption/facet heating/oxidation spiral). The technology is applicable to a range of material systems and has previously been demonstrated on InAlGaAs and InGaAs (increased COMD to >270 and 470mW/μm respectively). The devices with the typically lowest COMD levels (AlInGaAs) show a remarkably low linear degradation rate of <0.5%/kh during at CW life test operation at 90°C and a power level corresponding to 80W bar power. In addition to long term AlInGaAs laser life test results, this paper presents results on nitride facet passivation applied to 805nm InGaAsP devices, showing improved COMD to 400mW/μm and the initial CW life data confirms the general behavior of the previously life-tested InGaAs and InAlGaAs based devices.

A 200 h life test of nitride passivated AlInGaAs multimode lasers, with more than 20% aluminum, operating at 16 mW/μm, demonstrated a linear degradation rate of less than 0.1%/1000 h under stress conditions of 90 °C QW temperature and 2500 A/cm2 current density. No devices failed.

The 40-year-old laser diode technology underpins applications such as data storage, industrial lasers and telecommunications but still suffers from reliability and longevity issues in high power applications, most notably in pumping of Nd:YVO4 and Nd:YAG lasers. Despite thermal advantages allowing expansion matched Au/Sn hard soldering, the main problem for InAlGaAs lasers is facet oxidation, which leads to increased absorption and COMD device failure. This article presents a novel process, which atomically seals the surface and eliminates oxidation by forming stable nitrides on the facet. Pulsed testing of 805nm of Al>0.20InGaAs single mode devices with a protective nitride layer demonstrates stable median 1.3W COMD (30MW/cm(2)), after one hour of CW screening at 12.5mW/mum (50W bar power). A 200h burn-in at 12.5mW/mum (50W bar power) resulted in an initial power drop of 1-2% and a linear degradation rate of 0.1%/1000h, compared to an initial power drop of 5-18% and a degradation rate of 46%/1000h for lasers with only AR/HR-coatings. A subsequent 1000h life-test at 22.5mW/um (90W bar power) demonstrated a degradation rate of only 3%/1000h under stress test conditions due to p-side up mounting, 10degreesC higher ambient temperature and 57% higher operating current over typical high power bar operating power levels. The QW temperature was 53degreesC. No sudden device failures occurred.