Dissertations / Theses on the topic 'High light illumination'

Effective daylighting can substantially reduce the energy use and greenhouse gas emissions of commercial buildings. Daylight is also healthy for building occupants, and contributes to occupant satisfaction. When productivity improvements are considered, effective daylighting is also highly attractive financially. However, successful daylighting of sub-tropical buildings is a very difficult task, due to high direct irradiances and excessive solar shading. A device was created that combined effective solar shading and efficient daylight redirection. The micro-light guiding shade panel achieves all objectives of an optimal daylighting device placed on the façade of a sub-tropical, high rise office building. Its design is based on the principles of non-imaging optics. This provides highly efficient designs offering control over delivered illumination, within the constraints of the second law of thermodynamics. Micro-light guiding shade panels were constructed and installed on a test building. The tested devices delivered daylight deep into the building under all conditions. Some glare was experienced with a poorly chosen translucent material. Glare was eliminated by replacing this material. Construction of the panels could be improved by application of mass-manufacturing techniques including metal pressing. For the micro-light guiding shade panel to be utilised to its full potential, building designers must understand its impact on building performance early in the design process. Thus, the device must be modelled with lighting simulation software currently in use by building design firms. The device was successfully modelled by the RADIANCE lighting simulator. RADIANCE predictions compared well with measurements, providing bias generally less than 10%. Simulations greatly aided further development of the micro-light guiding shade panel. Several new RADIANCE algorithms were developed to improve daylight simulation in general.

Effective daylighting can substantially reduce the energy use and greenhouse gas emissions of commercial buildings. Daylight is also healthy for building occupants, and contributes to occupant satisfaction. When productivity improvements are considered, effective daylighting is also highly attractive financially. However, successful daylighting of sub-tropical buildings is a very difficult task, due to high direct irradiances and excessive solar shading. A device was created that combined effective solar shading and efficient daylight redirection. The micro-light guiding shade panel achieves all objectives of an optimal daylighting device placed on the façade of a sub-tropical, high rise office building. Its design is based on the principles of non-imaging optics. This provides highly efficient designs offering control over delivered illumination, within the constraints of the second law of thermodynamics. Micro-light guiding shade panels were constructed and installed on a test building. The tested devices delivered daylight deep into the building under all conditions. Some glare was experienced with a poorly chosen translucent material. Glare was eliminated by replacing this material. Construction of the panels could be improved by application of mass-manufacturing techniques including metal pressing. For the micro-light guiding shade panel to be utilised to its full potential, building designers must understand its impact on building performance early in the design process. Thus, the device must be modelled with lighting simulation software currently in use by building design firms. The device was successfully modelled by the RADIANCE lighting simulator. RADIANCE predictions compared well with measurements, providing bias generally less than 10%. Simulations greatly aided further development of the micro-light guiding shade panel. Several new RADIANCE algorithms were developed to improve daylight simulation in general.

L'objectif de cette thèse est de tirer parti d'une illumination totalement ou partiellement contrôlée pour enrichir l'acquisition vidéo de contenus tel que la reconstruction de la forme et de l'apparence. Aujourd'hui de nombreux travaux ont tenté d'atteindre cet objectif. Certains utilisent une illumination contrôlée et séquentielle pour obtenir des reconstructions de haute qualité de la forme et de la réflectance. En revanche, ces méthodes requièrent des dispositifs coûteuses et/ou ne fonctionnent pas en temps réel. Dans cette thèse, nous visions un système d'acquisition à bas coût, rapide et mobile, qui se veut non-seulement le moins intrusif possible mais aussi simple d'utilisation. La première contribution présentée dans cette thèse est une application de la méthode bien connue, intitulée stéréo photométrie, à la vidéo. De plus, comme une fréquence de trame élevée est nécessaire à une telle application, nous proposons une méthode permettant l'utilisation d'une illumination séquentielle avec des caméras rapides de type "electronic rolling shutter". Malgré les résultats intéressants obtenus, la qualité des reconstructions de l'apparence et de la forme n'étaient pas à la hauteur de nos espérances. De plus, la stéréo photométrie est une méthode qui, de nature, n'est pas très adaptée aux applications visées dans cette thèse. Pour notre seconde contribution, nous proposons une méthode de reconstruction de la forme (géométrie) ainsi que de la réflectance diffuse à partir d'une image (d'une séquence) en utilisant un système de capture hybride composé d'un capteur de profondeur (Kinect), d'une caméra grand public et d'un flash. L'objectif est de montrer qu'en combinant une acquisition RGB-D (image couleur + profondeur) avec illumination séquentielle, on peut obtenir une reconstruction qualitative de la forme et de la réflectance d'une scène dans le cas où l'éclairage n'est pas connu. Un couple d'images est capturé : une image non flashée (image sous une illumination ambiante) et une image flashée. Une image dont l'illumination ne provient que du flash (image flash pure) peut être calculée en soustrayant l'image non flashée de l'image flashée. Nous proposons un nouvel algorithme temps réel, qui, basé sur un modèle local d'illumination de notre flash et de l'image flash pure, améliore l'information de forme fournie par le capteur de profondeur tout en retrouvant les informations de réflectance diffuse. Notre dernière contribution concerne la composition automatique d'éclairage. L'éclairage est un élément clé de la photographie. Les professionnels travaillent régulièrement avec des systèmes d'éclairage complexes afin de capturer directement des images esthétiques. Récemment, certains photographes ont tenté une nouvelle approche : plutôt que photographier une scène directement sous un éclairage complexe, ils capturent la scène sous plusieurs éclairages simples, permettant ainsi un post-traitement permettant combiner les différentes illuminations de la scène. Cette approche apporte une nouvelle dimensionnalité intéressante au post-traitement. Cependant la combinaison des images requiert des compétences en matière de photographie, et l'acquisition sous différentes conditions d'éclairage n'en est pas moins fastidieuse. Nous proposons une méthode totalement automatisée, qui, à partir d'un modèle 3D (forme et albedo) reconstruit à partir de capture d'une scène réelle, produit virtuellement les images correspondant aux différentes conditions d'éclairages. Ensuite, ces images sont combinées automatiquement, à l'aide d'un algorithme génétique, pour correspondre à un style d'éclairage fourni par l'utilisateur sous forme d'une image cible de son choix
The objective of this thesis is to take advantage of controlled illumination to enrich a video acquisition with shape and reflectance reconstructions. Today, a lot of works have tried to meet this objective. Some of them take advantage of sequential controlled illumintation to recover high quality shape and reflectance, however they either require a costly and very cumbersome fixed setup, and/or do not run in real-time. Our aim is a low cost, fast, mobile and simple acquisition setup which has to be the less intrusive possible so as to provide a greater ease of use. The first contribution of this thesis focuses on the application of the well known photometric stereo method to a video acquisition. Moreover, as a high frame rate is required by such an application, a method using sequential illumination with high frame rate cameras (electronic rolling shutter cameras) is also considered. Despite the interesting results provided by photometric stereo, we found that this latter did not provide enough qualitative results. Moreover, by its nature, photometric stereo is not really suitable for the range of applications targeted. We propose, as a second contribution, a method for recovering the shape (geometry) and the diffuse reflectance from an image (or video) using a hybrid setup consisting of a depth sensor (Kinect), a consumer camera and a partially controlled illumination (using a flash). The objective is to show how combining RGB-D acquisition with a sequential illumination is useful for shape and reflectance recovery. A pair of two images are captured : one non flashed (image under ambient illumination) and a flashed one. A pure flash image is computed by subtracting the non flashed image from the flashed image. We propose a novel and near real-time algorithm, based on a local illumination model of our flash and the pure flash image, to enhance geometry (from the noisy depth map) and recover reflectance information. Finally, our last contribution concerns an automatic method for light compositing, using rendered images. Lighting is a key element in photography. Professional photographers often work with complex lighting setups to directly capture an image close to the targeted one. Some photographers reversed this traditional workflow. Indeed, they capture the scene under several lighting conditions, then combine the captured images to get the expected one. Acquiring such a set of images is a tedious task and combining them requires some skill in photography. We propose a fully automatic method, that renders, based on a 3D reconstructed model (shape and albedo), a set of images corresponding to several lighting conditions. The resulting images are combined using a genetic optimization algorithm to match the desired lighting provided by the user as an image

In live we often involve monitoring of very fast actions, that are not observable by the human eye. The thesis focuses on possibilities of high speed digital cameras, their application in industry, and the mechanism of chip formation. The experiment part aims to record the chosen process of chip machining and the problems of necessary illumination during the process of object imaging.

This PhD thesis is devoted to study electro-optic properties of Gemanium/Silicon-Germanium (Ge/SiGe) multiple quantum wells (MQWs) for light modulation, detection, and emission on Si platform. It reports the first development of high speed, low energy Ge/SiGe electro-absorption modulator in a waveguide configuration based on the quantum-confined Stark effect (QCSE), demonstrates the first Ge/SiGe photodiode with high speed performance compatible with 40 Gb/s data transmission, and realizes the first Ge/SiGe light emitting diode based on Ge direct gap transition at room temperature. Extensive DC and RF measurements were performed on each tested prototype, which was realized using the same epitaxial growth and fabrication process. Simple theoretical models were employed to describe experimental properties of the Ge/SiGe MQWs. The studies show that Ge/SiGe MQWs could potentially be employed as a new photonics platform for the development of a high speed optical link fully compatible with silicon technology.

碩士
國立臺灣科技大學
電子工程系
106
Due to the increasing global warming phenomenon in recent years, We need to reduce energy waste at present and find new energy sources to reduce the pollution to the environment for the sustainable development of mankind in the future, and solar energy is one of renewable energy. Many scholars have joined the development of sunlight. Among them, research has introduced natural light into the interior as a lighting and proposed the design of a Natural Light Illumination System(NLIS), which is beneficial to reduce the use of artificial lighting and lighting comfort requirements. The NLIS is composed of a light collecting, light transmitting, and light emitting subsystem. The collecting light system transmits the collected sunlight to the indoor light emitting subsystem through the light transmitting subsystem for green lighting. The system does not require additional energy conversion. It can effectively reduce the electricity consumption in the room. In the traditional Natural Light Illumination System, the light brick module light is transmitted by the optical fiber. However, the light brick module has four light exit ports, which require eight fibers to be coupled, and it is difficult to guide a large number of fibers to the erection. At the same time, it is easy to bend the fiber, which will cause the efficiency to drop. This study proposes an optical coupler that would improves the couple efficiency of the daylight collecting module in the Natural Light Illumination System. It uses the law of total reflection and double paraboloid confocal to compress the light twice and combine it for the light exit. We use this concept to reduce the use of fiber and indirectly improve the overall efficiency. Our simulation results show that the multi-stage series connection still has 66% efficiency at the 5th stage, and the new coupler effectively raises the tolerance angle. The coupler which used Natural Light Illumination System light source maintain 76%, it is 27% more efficient than the old coupler, and has an outstanding efficiency compared to the old coupler.

碩士
國立清華大學
動力機械工程學系
96
In this study, an optical design of the high power light emitting diode (HP LED) for illumination is proposed. A simplified structure of the LED that can use the lens to replace the reflector cup is designed. Therefore, the fabrication cost can be reduced. According to this design concept, a design method of the optical lens is developed. Based on the proposed method, an optical lens of the front-emitting HP LED to obtain a uniform illumination, and reduce the injured of the glare is designed. An optical model is used to obtain the overall point data of the lens profile by mathematics and geometrical optics base on the optical requirement. Either the straight lines or curves are used to draw the lens profile, and then rotate around the central axle to create the 3D optical model. In addition, the several lenses with same form but different scale are analyzed to find the optical properties of each lens in order to select a suitable size of the lens. The emission pattern of the lens is used to adjust the lens profile and each lens profile is analyzed to search the optimization lens profile by the uniformity of the illumination. Finally, an optical lens model with excellent illumination uniformity is found.

碩士
國立臺灣科技大學
電子工程系
97
White light LEDs have more advantages than those of traditional incandescent lamps and the fluorescent lamps; e.g. high stability, long life time and low power consuming etc. Therefore, white light LEDs have been regarded as the most potential light source of solid-state lighting (SSL) in the future. In this thesis, we focus on the white light LED optical design and illumination analyses. For the optical design issue, our purpose is to design a 300-Lux lamp on the work plane which is 2 meter away with LED with 4 square meters in size plane and has uniformity illumination. The luminous intensity distribution curve shape is a batwing distribution and the maximum luminous intensity around 27° which compares with 0° approximately is 0.71. We focus on the design of LED lens using the LightTools software to improve the light distribution of white light LED. After the luminous intensity distribution curve design is completed, the lamp needs nine LEDs to enable the work plane approximately to have 300 Lux. Next, we optimize the lamp to enhance the uniformity illumination on the work plane. The uniformity illumination is promoted to 0.9. For the illumination analysis issue, we use the LED lamp and the fluorescent lamp in the indoor space making the comparison. According to the comparison results, the utilization factor of the LED lamp is 0.682 higher than the utilization factor of the fluorescent lamp is 0.394. The LED lamp produces 100Lux which needs 2.29W is smaller than the fluorescent lamp produces 100Lux which needs 2.56W in the unit area (1m2). It proved that the LED lamp has low consumption when compares to that of the fluorescent lamp.

碩士
國立臺灣科技大學
電子工程系
105
In order to reduce the carbon dioxide emissions and reduce the level of global warming, renewable energy has become the development trend in which solar energy is inexhaustible. if the energy can be used not only save energy but also reduce carbon it will bring huge business opportunities. Therefore, National Taiwan University of Science and Technology Photonic Systems Simulation Design laboratory, PSSDL researches the sun into the indoor illumination for many years so that people will be able to enjoy healthy sunshine in the room and it can promote people's vitamin D and keep healthy both mentally and physically. Natural light illumination system is divided into four subsystems: pre-collecting, collecting, transmitting and irradiating. The pre-collecting track the sun which into the collecting system through the collecting system collects the next level of transmitting system and irradiating for indoor illumination. Due to the collecting system will continue reflection and refraction at interior cause scattered light as well as make the overall efficiency of the Natural Light Illumination System(NLIS) is not very well. In this paper, we design method of a free-form collimator is proposed. After Fresnel depletion, the strongest and sub-strong energy is selected. The collimator is designed by using the programmed grid cutting method and selecting complex light source is collimated by the slope of light spot with Cubic spline curve fitting also improve previously the efficiency of Natural light illumination system. Taking the freeform collimator of the 18496(1362) cutting grid as an example, the efficiency is 39.15% below 100 meters and compared to commercially available plastic fiber of PMMA materials, is up to about 39.08%.

碩士
國立臺灣科技大學
電子工程系
102
Nowadays, global warming has become a major issue. Reducing the consumption of fossil fuel and saving energy were the top priorities. In response to the energy crisis, renewable energy has been widely taken as other energy options. Solar energy is one of the most essential and abundant energy. If we can collect and transmit natural light into buildings without opto-electronic conversion, that will save energy and provide healthier light into our daily life. Therefore, our team designed a series of products known as Natural Light Illumination System (NLIS). In developing the high-quality NLIS, our primary concern was to increase the efficiency of the system. When the concentrators in daylight system collects sunlight, the light transmits through light pipe or fiber to any room you want. However, the efficiency decreases dramatically as the number of concentrator increases, due to the interconnection parts which encounter huge loss. For high-efficiency light transmission, the paper presents a design of coupler which assembles concentrators in module. The coupler consists of two structures, convergent element and light guide. According to the candle power distribution curve of the concentrator, we created the convergent element with multi-stage curvature. The concept of the multi-stage curvature is similar to the spherical surface which can compress sunlight smaller. Furthermore, the light guide gathered all light from concentrators and guided to the single exit port, which reduced the number of transmitting component. The module with coupler improved 23.29 % in efficiency with the same collecting area, which was 2.68 times higher. Furthermore, the lower transmitting components were not only lower cost and area but also easy to set up in the building or any place you want.

碩士
國立臺灣科技大學
電子工程系
101
Energy crisis and environmental pollution in recent years are increasing seriously, so energy-savings is the most critical issue currently faced by the globe. Especially for no pollution and has huge reserves of solar energy is of great concern by the people. We observed that during the day time, 30% of energy used as indoor lighting. In the application of healthy illumination, the industry and academics of every country design a system able to gather natural light for indoor lighting, namely, the Natural Light Illumination System. In order to reduce energy loss in light transmission, we in general want to make the optical coupler between the light collection and the light transmission. In this paper we have designed a optical coupler, which to collect sunlight for pass through the transmitter system. The optical coupler can integrate with the exits of the collectors and high transmission efficiency, most of all, the features of prism optical coupler make the coupler system easier to couple and reduce a lot of cost in transmitter.

碩士
逢甲大學
電機工程所
98
This research use the polarization optics and ZEMAX optical design software to design the light polarization conversion components which fully convert the polarization state of light for the illumination light of the projection system. This research use ZEMAX optical design software to design the polarization conversion components, and analyze the illumination and parallelism of light by TRACEPRO analysis software for finishing the design of high-efficiency polarized light illumination system in the LCD projector. The system specification are: 46 mm × 40 mm × 5 mm、the material of all the lens are BK7 and light source wavelength is 546.1 nm. The light doesn’t pass through PBS and wave retarder, its irradiance is 13.395 watts (44.65%); and the light pass through PBS and wave retarder with power(focal length is equal to 5 mm ), its irradiance is 19.007 watts (63.35%). This study not only demonstrated that through the reflector and the polarization conversion element can effectively improve the efficiency from 44.65% to 63.35%, but also constructed a compact light illumination system in the LCD projectors.

博士
國立中央大學
光電科學與工程學系
103
In this thesis, we have successfully analyzed optical performances on the basis of commercial high power pcW-LEDs. The analysis includes the étendue and exitance of the light source, and it can be utilized to estimate the quality of light sources to the illumination of projection lighting applications. In the thesis, a design of projection lamp with adjustable properties which can alter the light pattern. Accordingly, with well-designed secondary optical components, as well as proper LED light sources into the optical system, the highly optical performance can be achieved. On the other hand, the importance of the design of projection lamp with the high contrast property cannot be overestimated. Consequently, the thesis also considers the optical performances in LED light sources to fulfill the light pattern with high contrast and central illuminance. Finally, the estimation of white LDs with low étendue and high exitance has also been applied and analyzed for projection lighting.

碩士
國立清華大學
動力機械工程學系
97
The purpose of this research is to design a first-order（without other medium between lens and light source）lens of a high power light emitting diode(LED) for illumination. The manufacturing process of designed lens is also studied. The lens is designed to make the lights distributed on the objective surface as uniform as possible. The optical character of the light emitted from LED chip is lambertian emitting. The design algorithm of the light uniformity is obtained by means of reflection, total reflection and refraction. By using the optical mechanisms described above, we divided the light ray into small-angle ( light between optical axis ) light zone, and large-angle light zone. The computer is used to do the precise calculation to design the profile of the lens. To prove the design results is practical, several experiment are completed. In addition,, the production method is also considered. Considering the design of injection mold, the geometry and profile of the lens is modified and the optical performance of the modified lens is almost same as the original design. After the real lens fabricated, optical experiment is also proceeded. It is noted that due to the light of LED is not a point light source, therefore, the designed lens cannot reflect and refract every light ray in optimized way. It is necessary to use the optimum method to find the best lens profile.

碩士
國立臺灣科技大學
電子工程系
100
In recent years, green energy has undergone a lot of development and has been the subject of many applications. Many research studies have focused on illumination with sunlight as a means of saving energy and creating healthy lighting. Today, most daylight collectors use dynamic concentrators; these include Sun tracking systems. However, this design is too expensive to be cost effective. We have designed a static concentrator, which to collect sunlight for indoor illumination. Natural light illumination systems have collecting, transmitting, and lighting elements. This new natural light illumination system can effectively guide collected sunlight and send it to the basement or to other indoor places for healthy lighting, we have designed a high efficiency optical static lighting module applying the multiple-curvature structure to gather and convergence the collected sunlight from the natural light. There is a system able to gather natural light for indoor lighting, and it can increase more than 213% of the energy used by traditional lighting which only optic fiber.

La fosforilazione reversibile di proteine tilacoidali negli organismi fotosintetici è un meccanismo per far fronte a condizioni di luce variabili. Nelle monocotiledoni, contrariamente a quanto avviene nelle dicotiledoni, è stato dimostrato che la fosforilazione dell’antenna minore CP29, in seguito ad esposizione ad alte intensità luminose, induce un incremento in NPQ e diminuisce la produzione di specie reattive dell’ossigeno (ROS). La chinasi del complesso di antenne maggiori (LHCII), denominata STN7, e la relativa fosfatasi TAP38/PPH1, non partecipano in questo meccanismo, come in precedenza dimostrato nel nostro laboratorio, suggerendo l’ipotesi che un set di chinasi/fosfatasi differente fosse coinvolto nella regolazione di questo fenomeno. Recentemente, abbiamo analizzato un mutante knockout OsSTN8, gentilmente concessoci dal laboratorio di CH Lee, dimostrando che in aggiunta alla fosforilazione del core del Fotosistema II (PSII), anche quella di CP29 era soppressa, così provando che STN8 è la chinasi coinvolta nella fosforilazione di CP29 nelle monocotiledoni. Per meglio analizzare l’attività di OsSTN8 abbiamo trasformato linee mutanti di A. thaliana, dove il meccanismo di fosforilazione di CP29 in alta luce è assente, data la presenza di una libreria di mutanti molto vasta e dalla facilità con cui questa specie è geneticamente manipolabile rispetto a riso. I mutanti di A. thaliana stn8 e stn7stn8 complementati con OsSTN8 mostravano un recupero della fosforilazione del PSII core, come dimostrato tramite analisi Western blot. In aggiunta, la chinasi di riso fosforilava anche CP29 in condizioni di alta luce, contrariamente a quanto osservato nelle linee wild type. Misure di NPQ sono state eseguite sulle linee trasformate al fine di valutare l’effetto della fosforilazione dell’antenna minore sulla fotoprotezione. Un lieve incremento è stato osservato nelle linee trasformate con la chinasi di riso, indicando un possibile contributo di P-CP29 nella fotoprotezione in condizioni di di alta luce. Per meglio discernere il contributo di P-CP29 dalla fosforilazione del PSII core, mutanti Atlhcb4 sono stati co-trasformati con OsSTN8 e CP29 di riso o Arabidopsis, sia nella forma nativa che mutata al sito di fosforilazione Thr-83, ossia il sito identificato in riso come target della chinasi STN8. Un 6X-histag è stato addizionato alle proteine espresse per facilitare i processi di purificazione e permette analisi spettroscopiche delle forme fosforilate e non di CP29. Linee transgeniche sono state recentemente ottenute e misure fisiologiche saranno eseguite, sia in vivo che in vitro a seguito della purificazione della proteina. In A. thaliana la fosfatasi PBCP (Photosystem II Core Phosphatase) è stata dimostrata essere responsabile della defosforilazione del PSII core, controbilanciando l’attività di STN8. La proteina ricombinante OsPBCP da noi ottenuta era in grado di defosforilare in vitro sia le proteine del core che CP29 presenti nei tilacoidi e nelle preparazioni di complessi isolati da gradiente di saccarosio. Alla luce di questi risultati, abbiamo dimostrato che STN8 e CP29 sono, rispettivamente, la chinasi e fosfatasi coinvolte nella fosforilazione di CP29 nelle monocotiledoni, e OsSTN8 conserva la sua attività quando espressa in una dicotiledone come Arabidopsis thaliana.
Reversible phosphorylation of thylakoid proteins in photosynthetic organisms is a way to cope with changing light conditions. It has been demonstrated that in monocots, as opposed to dicots, upon high light exposure the minor antenna CP29 is phosphorylated enhancing NPQ and reducing singlet oxygen production. The major light-harvesting complex II (LHCII) kinase STN7 and its related phosphatase PPH1/TAP38 have been proven not to be involved in this mechanism in monocots, indicating that a different set of kinases/phosphatases act in regulating this acclimatory response. Recently, we have analyzed an OsSTN8 knockout mutant, kindly provided by the laboratory of CH Lee, in which we determined that in addition to that of the PSII core proteins, CP29 phosphorylation was suppressed as well, thus proving that STN8 is the kinase involved in CP29 phosphorylation in monocots. To further investigate OsSTN8 activity we transformed A.thaliana mutant lines, where CP29 phosphorylation is absent in high light, given the availability of mutant libraries and the ease with which this species is manipulable compared to rice. A.thaliana stn8 and stn7stn8 mutants transformed with OsSTN8 restored phosphorylation of the PSII core proteins, as confirmed through immunoblot analysis. Furthermore, the kinase was able to phosphorylate CP29 under high light conditions, as opposed to the wild type strain. Non-Photochemical Quenching (NPQ) measurements were performed on the transformed lines to assess the effect of the minor antenna phosphorylation on photoprotection, showing a mild increase in NPQ. To better understand the individual contribution of CP29 phosphorylation in transgenic Arabidopsis apart from that of PSII core phosphorylation in high light, knockout lines for Lhcb4 of A.thaliana were co-transformed in order to express OsSTN8 and CP29 either from rice or A.thaliana, both in its native and mutated form at Thr-83, site of phosphorylation in rice. A 6X-Histag was added for improved purification in order to conduct spectroscopic analyses on phosphorylated and unphosphorylated forms of CP29. Transgenic lines were recently obtained and physiological analyses will be performed in the near future, both in vivo and in vitro through purification of the protein. In A.thaliana the phosphatase PBCP was determined to be involved in PSII core dephosphorylation and counteract the effect of STN8. Our recombinant OsPBCP was capable of dephosphorylating in vitro both PSII core proteins and CP29, in thylakoids as well as isolated complexes from a sucrose gradient. In light of these results, we have determined that STN8 and PBCP are respectively the kinase and phosphatase involved in CP29 phosphorylation in monocots, and OsSTN8 retains its activity when expressed in a dicot such as Arabidopsis thaliana.