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Internet of thing (IoT) is a concept that aims to expand the benefits of internet connectivity that is connected continuously. Internet of things (IoT) can be used in buildings to control electronic equipment such as room lights that can be operated remotely via a computer network. This study aims to build a remote control device by utilizing internet technology to carry out the mobile-based light control process. The research was conducted by building a prototype and mobile-based application using the python programming language. In this study, there is a control feature, namely one light control which is used to turn on one lamp and two controls used to turn on the lamp simultaneously.

This paper presents the approach of an integrated system for lighting control on medical devices used in the treatment of Radiofrequency Ablation (RFA), which is applied for hepatic cancer. The principal approach in this case is videolaparoscopy, because it’s a minimally invasive surgery. One of the important components is the light source. The central idea is help to surgeon with the lighting control of light source used for visual camera with aim monitoring the evolution of ablation in liver and the possible complications that can appear by use RFA in organs or adjacent structures to liver. The purpose of this work is development a LED light source applied to RFA treatment for clinical applications. The light control reaches the minimal requirements of light in laparoscopic surgeries, in this case for a day light LED can to control the light of 0 up to 451 lm, for a white LED can to control the light of 0 up to 672 lm, these values are satisfactory for purpose of this work, and finally the verification was done by specialist physician in the area.

Delirium, the most common form of acute brain dysfunction affecting up to 80% of intensive care unit (ICU) patients, has been shown to predict long-term cognitive impairment, one of the domains in “Post-ICU Syndrome” (PICS). The ICU environment affects several potentially modifiable risk factors for delirium, such as disorientation and disruption, of the sleep–wake cycle. Innovative solutions aim to transform standard concepts of ICU room design to limit potential stressors, and utilizing the patient care space as a treatment tool, exerting positive, therapeutic effects. The main areas affected by most architectural and interior design modifications are sound environment, light control, floor planning, and room arrangement. Implementation of corresponding solutions is challenging considering the significant medical and technical demands of ICUs. This article discusses innovative concepts and promising approaches in ICU design that may be used to prevent stress and to support the healing process of patients, potentially limiting the impact of delirium and PICS.

Smart homes and Internet of Things are emerging concepts in modern society, with intelligent lighting being an important part of it. Besides providing visual satisfaction through its color-rendering properties, lighting also has other effects on human well-being. In order to exploit the full potential of a smartly lit home, lighting systems need to be equipped with accurate controllers that can control the spectrum and color characteristics of light in addition to conventional ON–OFF and dimming control. However, current commercial smart lighting products with such capabilities need to employ expensive sensors which are still lacking in terms of closed-loop feedback which is imperative for accurate color control of light-emitting diode (LED)-based luminaires. This paper presents a novel approach that uses the camera available on modern smartphones to perform closed-loop color control for lighting systems in smart homes. The algorithm is able to perform multi-channel mixing for any color and also white light at a desired correlated color temperature with high color-rendering index. This approach proves to be very economical and convenient as no external sensors are required and can be performed using any Android smartphone on a compatible LED-based luminaire.

Recent developments in the physics of high-index resonant dielectric nanostructures suggest alternative mechanisms for subwavelength light control driven by Mie resonances with a strong magnetic response that can be employed for the design of novel optical metasurfaces. Here we demonstrate metasurfaces based on nanoimprinted perovskite films optimized by alloying the organic cation part of perovskites. We reveal that such metasurfaces can exhibit a significant enhancement of both linear and nonlinear photoluminescence (up to 70 times) combined with advanced stability. Our results suggest a cost-effective approach based on nanoimprint lithography and combined with simple chemical reactions for creating a new generation of functional metasurfaces that may pave the way toward highly efficient planar optoelectronic metadevices.

Microoptics is a fast expanding field showing huge potential in providing science and industry with small yet highly functional tools for light control at a micro-scale. One of the most promising technologies to produce such elements is 3D laser lithography (3DLL) as it enables fabrication of free-form 3D objects with resolution and surface roughness control down to nm level [1]. So far it was employed to create integrated functioning monolithic 3D microoptical elements on functional substrates for in such applications as spatial light control [2] or imaging [3].

With the pervasion of LEDs and nowadays emerging Organic LEDs (OLEDs) automotive lighting has developed into an eye catching design element that gives the car a unique style and offers perceivable value to end customers. Light functions require animations, personalized patterns to attract end customers but they also can serve as a way to communicate with other cars and pedestrians, to increase safety. Such lighting systems imply new system architectures and enhanced network capability as well as a fast, robust and reliable communication interface from the central gateway to the light control unit hosting both the light sources and their own drivers. For this purpose, STMicroelectronics has developed a new communication standard - the CAN FD Light (*) - which implements all those features very attractive to all those car manufacturers who want to give their cars a classy unique look at competitive cost. This paper describes the innovation of automotive lighting with CAN FD Light bus and how it helps to achieve the automotive market requirements with a lean and robust solution. (*) CAN FD Light is filed for patent.

Photonic crystals have been widely used in solar cells in recent years because of their unique optical properties such as photonic band gap and “slow photon” effect. The introduction of photonic crystals can adjust the propagation and distribution of photons in solar cells. Therefore, a full understanding of the optical properties of photonic crystals and the correct use of photonic crystals are the key to improve the photoelectric conversion efficiency. At present, photonic crystal structures are widely used in dye sensitized solar cell (DSSC) and quantum dots sensitized solar cell (QDSSC), but relatively few in the field of perovskite solar cell (PSC). In this paper, the applications of different types of photonic crystals in silicon solar cells and sensitized solar cells are summarized, and the possible problems are analyzed and commented. It is pointed out that although photonic crystals have many excellent optical control properties, it is difficult to meet the thickness requirements of PSC due to the limitations of preparation technology and structure of photonic crystals. At present, the photoelectric conversion efficiency of photonic crystal PSC is generally low. Therefore, develop new technology for preparing the large area and high quality ultra-thin photonic crystals, make a profound study of photonic crystal light control mechanism, design new structures, and explore new functions of photonic crystals will become the future development direction of photonic crystal solar cells.

Standard headlights will shine with a fixed intensity even though the environmental light changes. High-intensity lights sometimes make other drivers glare and potentially cause accidents. Adaptive Light Control (ALC) is a car headlights control system that can automatically adjust the intensity of the lamp according to the intensity of the light environment. In this research, we developed ALC which was able to regulate the intensity of the lamp according to the intensity of the environmental light including the light of the car in front. Light settings are performed using a fuzzy control system by utilising environmental light intensity and the distance of the car to the object as input. The developed ALC system was tested on remote control cars equipped with sensors and microcontrollers. The intensity of headlight begins to fade on the distance of the car to the object of 92 cm for objects in front of, 108 cm for objects on the left, and 22 cm for objects on the right.

Lasers and anti-lasers (time-reversed counterpart of lasers) are critical for the generation and absorption of coherent light beams. Here we experimentally demonstrate on-chip switchable lasing and anti-lasing in a single photonic cavity using the concept of parity-time symmetry. This opens the door for extreme light control towards the ultimate limit of modulation depth.

Advances in the measurement and manipulation of light’s spatiotemporal properties are overcoming many of the practical difficulties which have traditionally limited the applications of multimode optical fiber.

Conoscopy is the visualisation of the birefringence of materials using depolarisation of light passing through with a broad range of incident orientations. In recent years, conoscopy has become an important optical tool in the science of soft materials, such as liquid crystals and polymers, and is widely applied in materials engineering and development, for example in technologies ranging from display optics to plastic food packaging. This paper reports ‘fisheye lens conoscopy’, a fundamentally new and broadly applicable optical approach to conoscopy that is particularly appropriate for the study of soft materials. These capabilities are illustrated using a fisheye lens system to characterise birefringent and polarising polymer films and liquid crystal test cells. In addition to birefringence measurement, fisheye conoscopic determination of the emission characteristics of commercial light emitting devices such as liquid crystal displays and the transmission of topographically patterned light control films...

A study on the attraction of adult Propsilocerus akamusi midges to different-colored light traps was carried out from October 21 to November 15, 2013. The 6 colored lights used in light-emitting diode (LED) lamps were white, green, red, blue, amber, and ultraviolet (UV). The UV lamp attracted the most P. akamusi, followed by green, white, blue, amber, and red. A white pulsed LED light attracted only half the number of midges as did a continuous-emission white LED light. The result indicated that manipulation of light color, considering that the red LED light and/or pulsed LED light are not as attractive as the other colors, may be appropriate for the development of an overall integrated strategy to control nuisance P. akamusi in the Lake Suwa area.

High-index resonant dielectric metasurfaces suggest alternative mechanisms for subwavelength light control and can consist of broad range of dielectric materials with various functionality. Here we demonstrate metasurfaces based on nano imprinted perovskite films optimized by alloying the organic cation part of perovskites. Our results suggest a cost-effective approach based on nanoimprint lithography and combined with simple chemical reactions for creating a new generation of functional metasurfaces which may pave a way towards highly efficient planar optoelectronic meta devices.

The ability of metasurfaces to manipulate light at the subwavelength scale offers unprecedented functionalities for passive and active lasing devices. However, applications of metasurfaces to optical devices are rare due to fabrication difficulties. Here, we present quantum dot light emitting diodes (QDLEDs) with a metasurface-integrated metal electrode and demonstrate microscopically controlled LED emission. By incorporating slot-groove antennas into the metal electrode, we show that LED emission from randomly polarized QD sources can be polarized and directed at will. Utilizing the relation between polarization and emission direction, we also demonstrate microscopic LED beam splitting through the selective choice of polarization.

We demonstrate composite, multiplexed 3D metamaterials for functional light manipulation. Applications include multi-wavelength achromatic metalenses in the visible spectral range, integrated elements for STED microscopy, and nonlinear holography. Prospects for novel applications are discussed.

This paper focus on the features of half power saving in city road lighting LED retrofits , presences a light control and time-lapse switch LED lights control scheme, use photoresistor, 555 time base circuit and CD4060 binary counter, realized the control circuit design. The experimental results show that the proposed scheme in this paper is simple, practical and reliable.

The article describes the application of microcontroller PIC18F25K22 to servomechanism electronics built – in the model of car. Model is controlled optically, in the infrared part of the spectrum. Used microcontroller is optimal for this application – it has timers with capture facilities, sufficient number of PWMs, powerfull instruction set. The main task for microcontroller is to process incoming PWM signals S1, S2 (having jitter) into output PWM signals P1, P2 (jitter free). The P1 controls the angle of wheels, and the P2 handles the speed. Values of incoming signals are continuously summarized and rounded. There was choiced method of hysterezis in sophisticated algorithm for setting output PWM signals P1, P2 using tables of duties.

In this paper, ZigBee-VLC Transmitter and Receiver are designed, implemented and tested. By utilizing the ZigBee-VLC Transmitter and Receiver, commissioning procedures for light control network configuration are simplified and commissioning time is drastically reduced. With this configuration, lighting control network configured to use a maximum of 216 lighting is possible. As a result of this research, the transmitter is complete with ZigBee-VLC features implemented in the Single MCU without rising production costs and the 1-board solution receiver including a ZigBee and VLC functions are implemented. In addition, as a result of the test work using the light control app, dramatically shortening commissioning time, easy lighting control is possible was confirmed.

I will present some of our recent efforts in addressing the challenge of imaging and light control through, inside, and around scattering media and optical fibers.

With the unique possibilities for controlling light in nanoscale devices, graphene plasmonics has opened new perspectives to the nanophotonics community with potential applications in metamaterials, modulators, photodetectors, and sensors. This paper briefly reviews the recent exciting progress in graphene plasmonics. We begin with a general description for optical properties of graphene, particularly focusing on the dispersion of graphene-plasmon polaritons. The dispersion relation of graphene-plasmon polaritons of spatially extended graphene is expressed in terms of the local response limit with intraband contribution. With this theoretical foundation of graphene-plasmon polaritons, we then discuss recent exciting progress, paying specific attention to the following topics: excitation of graphene plasmon polaritons, electron-phonon interactions in graphene on polar substrates, and tunable graphene plasmonics with applications in modulators and sensors. Finally, we seek to address some of the apparent challenges and promising perspectives of graphene plasmonics., Comment: Invited minireview paper on graphene plasmon polaritons, 11 pages, 4 figures

Recent studies have found that LED technology is becoming competitive for streetlight applications compared with commonly employed high-intensity discharge light sources, such as high-pressure sodium (HPS) and metal halide. The expectation is that LED street lighting technology will not only provide more efficient light distribution and increased uniformity but will also save energy and reduce maintenance costs. Seattle City Light (SCL), Washington, has a street lighting system of nearly 84,000 street and area lights that predominantly use HPS light sources. Because of the potential benefits of installing LED luminaires as replacements for these lights, SCL launched the LED Streetlight Application Assessment Project pilot study to evaluate LED luminaires for photometric performance, energy efficiency, economic performance, and other impacts on the SCL streetlight system. The project findings will be used by SCL to create a strategy for the installation of LED streetlights to develop an energy-efficient lighting system. The major elements of this project included LED luminaire selection, simulated photometric performance evaluation of selected LED products, field photometric performance evaluation at selected test sites, and economic performance evaluation in comparison with HPS luminaires. In addition, because combining LED roadway luminaires with new light control systems provides many new options to enhance overall light control, facilitate maintenance, increase luminaire life, and reduce operating costs, a preliminary review of current cutting-edge lighting control systems was conducted.

A system for inspecting flat panel displays (FPDs) acquires scanning images using multiline charge-coupled device (CCD) cameras and industrial machine vision. Optical filters are currently installed in front of these inspection systems to obtain high-quality images. However, the combination of optical filters required is determined manually and by using empirical methods, this is referred to as passive color control. In this study, active color control is proposed for inspecting FPDs. This inspection scheme requires the scanning of images, which is achieved using a mixed color light source and a mixing algorithm. The light source utilizes high-power light emitting diodes (LEDs) of multiple colors and a communication port to dim their level. Mixed light illuminates an active-matrix organic light-emitting diode (AMOLED) panel after passing through a beam expander and after being shaped into a line beam. The image quality is then evaluated using the Tenenbaum gradient after intensity calibration of the scanning images. The dimming levels are determined using the simplex search method which maximizes the image quality. The color of the light was varied after every scan of an AMOLED panel, and the variation was iterated until the image quality approached a local maximization. The number of scans performed was less than 225, while the number of dimming level combinations was 20484. The proposed method can reduce manual tasks in setting-up inspection machines, and hence is useful for the inspection machines in FPD processes.

A tuning method was proposed for automatic lighting (auto-lighting) algorithms derived from the steepest descent and conjugate gradient methods. The auto-lighting algorithms maximize the image quality of the industrial machine vision by adjusting multiple-color light emitting diodes (LEDs), usually called color mixers. Searching for the driving condition for achieving maximum sharpness, which influences image quality, using multiple color LEDs, is time-consuming. Hence, the steepest descent and conjugate gradient methods were applied to reduce the searching time for achieving maximum image quality. The relationship between lighting and image quality is multi-dimensional, non-linear, and difficult to describe using mathematical equations. Hence the Taguchi method is actually the only method that can determine the parameters of auto-lighting algorithms. The Taguchi method was applied to an inspection system consisting of an industrial camera, coaxial lens, color mixer, image acquisition device, analog interface board, and semiconductor patterns for target objects. The algorithm parameters were determined using orthogonal arrays and the candidate parameters were selected by increasing the sharpness and decreasing the iterations of the algorithm, which were dependent on the searching time. After conducting retests using the selected parameters, the image quality was almost the same as that in the best-case parameters with a smaller number of iterations. The Taguchi method will be useful in reducing time-consuming tasks and the time required to set up the inspection process in manufacturing.Copyright © 2015 by ASME

A multidirectional asymmetrical microlens array light control film (MAMA-LCF) which can direct light incident from multiple directions collectively for viewing is demonstrated in achieving much enhanced brightness in reflective color super twisted-nematic liquid crystal displays (STN-LCDs). The MAMA-LCF, constructed with an asymmetrical microlens array and laminated onto the front surface of reflective color STN-LCDs, can yield a maximum gain of about 5× the MgO standard white in a typical viewing region without visible dispersion, moire or parallax effects.

After a brief review of the basic properties of ideal two-dimensional photonic crystals, we describe the recent advances that have led to them being considered candidates in realistic, feasible optoelectronic systems that take advantage of their powerful light control capability. Two main fields of applications are integrated optics and microstructured fibres. We focus on the former one, closer to the genuine photonic gap concept. We illustrate through a number of optical elements – simple crystals, guides and cavities – the peculiarities of confinement by such systems. To cite this article: H. Benisty et al., C. R. Physique 3 (2002) 89–102

To make photolithography patterns on 3D samples, the angled (inclined) exposure technique has been used so far. However, technological issues have emerged in making photolithography patterns on the surface of trench structures. The surface of the trench structures can be covered with a photoresist film by spray-coating but the photoresist film deposited on the sidewalls and bottom of the trench is generally thin. The thin photoresist film deposited inside the trench has been easily overdosed. Moreover, irregular patterns have frequently been formed by the light reflected inside the trench. In this study, we have developed liquid immersion photolithography using a light-absorbent material. The light-reflection inside the trench was suppressed. Various patterns were transferred in the photoresist film deposited on the trench structures which had an aspect ratio of 0.74. Compared to immersion photolithography using pure water under p-polarization light control, the light-absorbent liquid immersion photolithography developed here patterned well the surfaces of the trench sidewalls and bottom.

In this paper, we propose and implement a medical support system considering P2P and IoT technologies. We used our implemented smart device that we call Smart Box. We have implemented in the Smart Box many functions and sensor such as body sensor, infrared sensor, chair or bed vibration control, light control, smell control and sound control. By using Smart Box the implemented system is able to control the situation of patients. We carried out experiments to evaluate the implemented system. The evaluation results show that the implemented system can detect the patient situation.

The use of high-power LEDs for street lighting is growing continuously due to their greater energy efficiency, robustness, long life and light control. The possibly higher harmonic emission from these lamps has been mentioned however as a drawback. Not only is it important to know the individual harmonic emission of every device connected to the PCC, but it is also necessary to know the impact after the harmonic aggregation of those devices. In this paper, the harmonic emission of HPS lamps with electronic ballasts and LED street lamps has been studied. Different approaches on estimating the emission from multiple lamps are compared. The approach according to IEC 61000-3-6 has been compared with measurements, showing the limitations of that approach. Godkänd; 2014; 20130616 (matbol)

This paper introduces a system that can effectively save home energy by applying a small embedded system through remote control. We used a wireless router based on OpenWrt for the platform to develop an embedded system and a smart phone for the remote LED light control. The system was implemented by connecting a wireless router with an OS of OpenWrt installed and an interface board with an LED attached. The smart phone, which was the remote control device, was implemented by TCP/IP programming. The operation of the remote control system was verified by socket communication between the smart phone and the wireless router, and by USB communication between the wireless router and the interface board.

The exposure time and signal gain can be used to adjust the light intensity for a conventional CCD camera, but both of them can not be configured best. It is also very difficult to maximize the effectiveness of their dimming, especially for the condition of the changed illumination intensity, the large dynamic range and the unclear picture. For the above-mentioned shortages, the histogram equalization certain improvements, the deployment of exposure time and signal gain were optimized through precise deployment of exposure time and optimization of signal gain coefficients. After the test, the screen effect has been significantly improved, the adjustment time is less than 40 ms, and the system is stable and reliable. © 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved.

In any conference/seminar hall, whenever a speaker/presenter wants to switch over from projected presentation to white maker board due to some audience query, someone has to physically monitor the speaker activity and then control the lights accordingly. This paper tries to automate this activity by using Projector Light Controller Module (PLCM) which consists of 180∘ continuous rotating ultrasound sensor that senses the presence of the speaker near the white marker board and send this information via RF wireless communication to the light control system for decision making to automatically turn ON the light. As the speaker moves away from the white marker board, lights will be automatically turned off. This design will take care of two adjacent white markers board in the conference/seminar hall, to turn ON the lights of respective white marker board.

We address light propagation in segmented waveguide arrays where the refractive index is longitudinally modulated with an out-of-phase modulation in adjacent waveguides, so that the coupling strength varies along propagation direction. Thus in resonant segments coupling may be inhibited hence light remains localized, while in detuned segments coupling results in complex switching scenarios that may be controlled by stacking several resonant and nonresonant segments. By tuning the modulation frequency and lengths of waveguide segments one may control the distribution of light among the output guides, including loca-lizing all light in the selected output channel., Comment: 12 pages, 4 figures, to appear in Europhysics Letters

A cost-efficient light control system based on weather forecasts, electricity prices and daily photosynthesis integral (DPI) was evaluated for application in the commercial production of the long-day (LD) plant Campanula portenschlagiana ‘Blue Get Mee’ and C. cochlearifolia ‘Blue Wonder’. Experiments were conducted under both autumn and spring conditions and included four treatments. Three treatments were controlled by the software system DynaLight Desktop which automatically defined the most costefficient use of supplemental light, -based on a predefined set point of DPI, forecasted solar irradiance and the market price on electricity. The set points of DPI in the three treatments were 300, 450 and 600 mmol CO2 m−2 leaf d−1 and the treatments were compared with a traditional LD 19-h treatment. The DPI-based light control strategy resulted in very irregular light patterns including daily periods of solar irradiance combined with supplemental light in low light periods and a night period interrupted by irregular light breaks (NB-lighting). Both campanula species flowered in the DPI-based treatments during spring, but the flowering percentage was low and non-uniform during autumn. This was caused by a combination of the irregular light, low natural light intensities and a decrease in daily light integral (DLI), and couldbe restored by maintaining a continuous 19 h photoperiod with incandescent lamps (in electricity costs was achieved without major reductions in plant quality in spring. Our results illustrate that plant production of LD species can be maintained in a cost-efficient light control system where the use of supplemental light is based on weather forecasts and electricity prices.

Thin film coatings modulate optical and thermal and other properties of window glass. Coated window glasses influence indoor climate and energy efficiency in buildings. They can be classified into groups of spectrally selective glazings, chromogenic glazed systems for switchable smart window technologies and light-enhancing transparent materials. Low-emissivity glazings are typical of spectrally selective window glasses. Chromogenics have applications in light control and switching technologies that are optically, thermally, chemically or electrically activated. Transparent materials with micro-structured or holographic films and antireflective coatings serve to direct light and control light functions. An overview of several types of window glazings and coatings will be presented.

An off-axis asymmetrical microlens array light control film (AMA-LCF) for brightness and contrast enhancement in reflective liquid crystal displays (LCDs) is demonstrated. The AMA-LCF is laminated to the top surface of the reflective LCDs, and directs incident light into a reflected cone near normal to the display surface, yielding a gain about 1X to 10X of MgO standard-white at the typical viewing region from 0° to 20°. Moreover, glare can be greatly reduced.

Solid state lighting offers a lot of novel prospects for tomorrows customized lighting solutions. None the less, to compete with and to surpass the performance of the traditional lighting systems, design and development of LED light sources is still facing the necessity of further improvements, in particular with respect to device efficiency and light control. In this contribution we discuss recent developments and novel strategies in order to improve the light extraction efficiency as well as to affect the directionality of the light emitted from high power LEDs. In order to be up to characterize these modifications with high spatial resolution, novel characterization techniques, like the implementation of a confocal principle into the measurement set-up are discussed.

Unless coupled with some collimating optics, LED sources generally scatter with wide-angle Lambertian intensity profiles. The luminous output of such sources is not amenable to control and redistribution in an efficient manner. In this work we present the design and manufacturing of structures that are able to collect virtually all light from Lambertian LED sources and direct it towards diffusers engineered to illuminate specific regions of space in a controlled fashion. The resulting "engineered luminaire" is thus capable of highly efficient light control and can be applied to a wide variety of illumination situations such as general and architectural lighting.

Multidirectional asymmetrical microlens array light control films were developed to enhance image quality of reflective LCDs. Significant gain in both brightness and contrast ratio has been demonstrated without visible surface diffusion, Moire patterns and parallax.

Certain individuals with cerebral palsy communicate using a head-mounted device wherein they can press computer keys, etc. The Tap-Tap environmental controller adapts this method of communication into device that facilitates household appliance control via touchpad circuitry.

Readability on a mobile LCD can be improved by dynamically adapting the display's intensity to the ambient illumination. A study was performed to investigate how fast to adapt the display's intensity when switching between bright and dark environments, such that people have good readability, and do not perceive display flicker.

A reflective liquid crystal display (R-LCD) has become an important component of a portable information device; however, its inadequate whiteness appearance is a major issue in achieving the potential of “electronic paper”. The factors causing inadequate whiteness were examined using a conventional R-LCD. Furthermore, a novel reflectance-profile-controlled component “random grating light control film” and a non dispersed LC mode with a high-cell-gap tolerance were presented to achieve the paper-white image of reflective LCDs.

The multidirectional asymmetrical microlens array light control film (MAMA-LCF) is developed to enhance the image brightness and contrast ratio of reflective liquid crystal displays. Through optimized designs and optical alignments, the MAMA-LCF which is constructed with asymmetrical microlens arrays, leads to a ∼5× gain in brightness over the MgO standard white and 12:1 contrast ratio for color STN-LCDs, 10× gain and 11.5:1 contrast ratio for PDLC, and 9× gain over the conventional Ch-LCD. In each display, the light control film does not induce visible surface diffusion, moire patterns and parallax.

A Multi-directional Asymmetrical Microlens Array Light Control Film (MAMA-LCF) which can direct the incident light from multi-direction for viewing is demonstracted for much enhanced brightness in reflective color super-twisted-nematic liquid crystal displays (STN-LCDs). The MAMA-LCF, constructed with an asymmetrical microlens array and laminated onto the front surface of the reflective color STN-LCDs, can yield a maximum gain about 20× of MgO standard-white in a typical viewing region without visible Morie and prallax effects.