Intel Corporation

Robert A Carney

Douglas A Sprock

George Pontis

Rajesh K Batra

Kenneth P Koller

Ken P Koller

David K Thiesen

Timothy L Robertson

An apparatus including a reference resistor for use with ratiometric temperature sensing of a device to be sensed. The resistive element has a resistance dependant upon a temperature of the device to be sensed and is electrically coupled to a reference resistor. The reference resistor is maintained at a substantially constant temperature by a temperature controller. A sensor circuit is electrically coupled to the resistive element and the reference resistor to sense their electrical parameters when a current passes through them.

Remote reference resistor

A laser system including a controller for monitoring and controlling various functions of a laser assembly. The laser controller may include a wavelength tuning circuit for adjusting and locking the wavelength of the external cavity. To perform various monitoring and control functions, the controller may include circuitry for monitoring various parameters associated with operation of the laser, such as temperature indicating signals and/or signals from light detectors such as photodiodes.

Tunable laser with wavelength locking

In one embodiment of the present invention, an apparatus operates a control loop for a tunable optical device. A digital reference signal is converted to an analog reference signal and then introduced into the optical path of the tunable optical device. An analog feedback signal, corresponding to the digital reference signal, is recovered from the tunable optical device. The analog feedback signal is converted to a digital feedback signal. The apparatus sends tuning information to the tunable optical device based on analysis of the digital reference signal and the digital feedback signal. In one embodiment, the tuning information is used for wavelength locking of the tunable optical device. In another embodiment, the operation of the control loop is synchronized with another function of the tunable optical device.

Interrupt driven wavelength locking

Tunable laser and laser current source

Tunable laser temperature sensing control system

Tunable laser systems use servo control loops to control and monitor laser parameters such as channel, temperature, and power. The many control loops operate asynchronously, which means that noise generated by input sampling and/or output updating from one or more loops could interfere with the sampled inputs of one or more of the other loops. Embodiments of the present invention synchronize setting and sampling of tunable laser parameters to reduce noise. Noise that is related to synchronized setting and sampling of tunable laser parameters allows the noise to be reduced to constant offsets to be compensated for in the laser parameters of interest.

Synchronous servo control for a tunable laser

Tunable laser control system with optical path length modulation

A tunable optical unit includes a resistive temperature device (RTD), a thermal tuning device and a measurement circuit. The RTD has a resistance dependent on a temperature of the thermal tuning device. The measurement circuit outputs a signal that is dependent on the resistance of the RTD. The signal is used to control the temperature of the thermal tuning device in tuning the tunable optical unit. A reference resistance can be connected in series with the RTD to make ratio-metric measurements to determine the RTD's resistance (and hence the temperature of the tuning elements) without having to know the value of the current conducted through the RTD and to reduce sensitivity to fluctuations in the excitation signal.

Growing community of inventors

Belmont, CA, United States of America

Robert A Carney