Researchers at the University of California, Davis (“UC Davis”) have developed an optical absorber/emitter for thermophotovoltaics application with a tunable emission wavelength.

      Goniophotometers measure the luminance distribution of light emitted or reflected from a point in space or a material sample. Increasingly there is a need for such measurements in real-time, and in real-world situations, for example, for daylight monitoring or harvesting in commercial and residential buildings, design and optimization of greenhouses, and testing laser and display components for AR/VR and autonomous vehicles, to name a few. However, current goniophotometers are ill-suited for real-time measurements; mechanical scanning goniophotometers have a large form factor and slow acquisition times. Parallel goniophotometers take faster measurements but suffer from complexity, expense, and limited angular view ranges (dioptric angular mapping systems) or strict form factor and sample positioning requirements (catadioptric angular mapping systems). Overall, current goniophotometers are therefore limited to in-lab environments.      To overcome these challenges, UC Berkeley researchers have invented an optical sensor  for parallel goniophotometry that is compact, cost-effective, and capable of real-time daylight monitoring. The novel optical design addresses key size and flexibility constraints of current state-of-the-art catadioptric angular mapping systems, while maximizing the view angle measurement at 90°. This camera-like, angular mapping device could be deployed at many points within a building to measure reflected light from fenestrations, in agricultural greenhouses or solar farms for real-time monitoring, and in any industry benefitting from real-time daylight data.

The California Lighting Technology Center at UC Davis in collaboration with the Center for Mind and Brain have developed a novel lighting technology approach for stress recovery and stress mitigation.

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In developed countries, buildings demand a large percentage of a region's energy-generating requirements. This has led to an urgent need for efficient buildings with reduced energy requirements. In office buildings, lighting takes up 20% to 45% of the total energy consumption. Furthermore, the adoption of smart lighting control strategies such as daylight harvesting is shown to reduce lighting energy use by 30% to 50%.For most closed-loop lighting control systems, the real-time data of the daylight level at areas of interest (e.g., the office workbench) are the most important inputs. Current state-of-the-art solutions use dense arrays of luxmeters (photosensors) to monitor the daylight environment inside buildings. The luxmeters are placed on either workbenches, or ceilings and walls near working areas. Digital cameras are used in controlled laboratory environments and occasionally in common buildings to evaluate glare resulting from excessive daylight. The disadvantage of these sensor-based approaches is that they're expensive to install and commission. Additionally, the sample area of these sensors is limited to either the area of the luxmeters or the view of the cameras. Consequently, many sensors are needed to measure the daylight in a large office space.To address this situation, researchers at UC Berkeley developed a portable cyber-physical system for real time, daylight evaluation in buildings, agriculture facilities, and solar farms (collectively referred to as "structures").

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A new structure for III-N transistors that is able to maintain a high breakdown and operating voltage while improving the gain of the device.

A structure for improving the performance and reliability of III-nitride based tunnel junction optoelectronic devices.

A surface treatment that can shape the electric field profile in electronic devices in 1, 2, or 3 dimensions.

An m-plane VCSEL with an active region that has thick quantum wells and operation in continuous wave.

Methods of physical vapor deposition for III-nitride tunnel junction devices.

Prof. Yang and colleagues have developed a novel method of preparing organic-inorganic thin films using a solution process followed by vapor treatment, presenting a low-cost, high-performance solution method of producing optoelectronic devices.

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A method for generating a stand-alone ceramic phosphor composite for use in solid state white light generating devices that successfully reduces the operating temperature of the phosphor material by 50%, increases lumen output, reduces cost of materials, and decreases preparation time.

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A method to control the anisotrophy of strain in semipolar nitride-based active layers of optoelectronic devices while maintaining high device performance and efficiency.

A nonpolar III-nitride LED or LD that does not require any aluminum-containing cladding layers, because the quantum well active region is thick enough to function as an optical waveguide for the device.  

Polarized white LEDs that can improve system efficiency by removing the need for an external polarizer.

A method to grow semipolar (Ga, Al, In, B)N thin films, heterostructures, and devices on suitable substrates or planar templates in which a large area of the semipolar film is parallel to the substrate surface. 

Minimizes the re-absorption of LED light by using transparent conductive oxide electrodes (ITO or ZnO) instead of mirrors. 

A solid state white lighting device consisting of a blue laser diode that emits light onto a single crystal phosphor, resulting in the emission of high-intensity white light. 

A method for enhancing the growth of semipolar nitride films using either a buffer layer or a nucleation layer. 

A method using MOCVD growth conditions to achieve high performance m-plane GaN optical devices, including LEDs and LDs.