Illumination Parameters Research Articles

Hybrid full-pose parameter calibration of a freeform illuminator for Fourier ptychographic microscopy.

As a typical computational method, Fourier ptychographic microscopy (FPM) can realize high spatial resolution and quantitative phase imaging while preserving the large field of view with a low numerical aperture (NA) objective. A programmable light-emitting diode (LED) array is used as a typical illuminator in an FPM system, and the illumination parameters of each LED element are crucial to the success of the FPM reconstruction algorithm. Compared with LED arrays arranged in rectangular arrays, LED arrays with special structures such as domes or rings can effectively improve FPM imaging results and imaging efficiency. As a trade-off, their calibration difficulty is greatly increased due to the lack of geometric constraints of rectangular arrays. In this paper, we propose an effective hybrid full-pose parameter calibration method for freeform LED array illuminators, combining stereoscopic 3D imaging techniques and the geometric constraints of the microscopic platform. First, a stereovision system is used to obtain the accurate 3D position of each LED element of the freeform illuminator and to construct a rigid 3D coordinate LED array system. Then, calibration between the coordinate system of the LED array and that of the optical imaging component is realized according to the geometric features of the brightfield-to-darkfield edges. Finally, we verify the feasibility and effectiveness of the proposed method through full-pose parameter calibration of LED arrays with different arrangement rules.

Illumination-guided inverse rendering benchmark: Learning real objects with few cameras

The realm of 3D computer vision and graphics has experienced exponential growth recently, enabling the creation of realistic virtual environments and digital representations of real-world objects. Central to this progression are 3D reconstruction methods that facilitate the virtualization of shape, color, and surface details of real objects. Current methods predominantly employ neural scene representations, which despite their efficacy, grapple with limitations such as necessitating a high number of captured images and the complexity of transforming these representations into explicit geometric forms.An alternative strategy that has gained traction is the deployment of methods such as physically-based differentiable rendering (PBDR) and inverse rendering. These approaches require fewer viewpoints, yield explicit format results, and ensure a smoother transition to other representation methods. To meaningfully assess the performance of different 3D reconstruction methods, it is imperative to utilize benchmark scenes for comparison.Despite the existence of standard objects and scenes within the literature, there is a noticeable deficiency in real-world benchmark data that concurrently captures camera, illumination, and scene parameters — all critical to high-fidelity 3D reconstructions using PBDR and inverse rendering-based methods. In this research, we introduce a methodology for capturing real-world scenes as virtual scenes, integrating illumination parameters alongside camera and scene parameters to enhance the veracity of virtual representations. In addition, we introduce a set of ten real-world scenes, along with their virtual counterparts, designed as benchmarks. These benchmarks encompass a fundamental variety of geometric constructs, including convex, concave, plain, and mixed surfaces. Additionally, we demonstrate the 3D reconstruction results of state-of-the-art 3D reconstruction methods employing PBDR in real-world scenes, using both established methodologies and our proposed one.

Photoepilation with high power LED - holonyak: evaluation of efficacy, satisfaction and incidence of side-effects

Background: Devices that use light, especially lasers, have become popular and are commonly used in aesthetics and hair removal. Laser-assisted photo epilation was originally described in 1996 and the proposed mechanism is based on the destruction of the follicular unit. Diode laser has been demonstrated to be an effective method for hair removal, however, the safety of patients with different skin types and colours is questionable due to thermal damage as the main side-effect. In this sense, the technological innovation of Photoepilation using high power LED equipment with high head cooling efficiency represents a great advance for the area. In this work, we evaluated the results of photoepilation using high-power LED in 117 patients with phototypes 01 to 06. Methods: A High potency LED equipment (Holoniak® – Adoxy Equipments – Brazil) was used. The LED allows the therapist to customize illumination parameters according to the sensitivity of the patients. All 117 participants were submitted to an initial sensitivity test to the LED irradiation, in order to determine adequate parameters to each participant. Sensitivity test was performed in both stationary and scanning modes. In scanning mode the test started with the following parameters – temperature of the at 10oC, fluence of 5 J/Cm2 and frequency 2 – 3 Hz. In stationary mode the sensitivity test started with temperature of the probe at 10 oC, fluence of 10 J/Cm2 and frequency of 0.8 Hz. No phototype restrictions were applied. To analyze the satisfaction of results, we created an arbitrary scale ranging from 1 to 4, where Grade 1 was considered unsatisfactory, Grade 2 - little satisfactory, Grade 3 - satisfactory and Grade 4 - very satisfactory. We also analyzed the number of sessions needed to achieve the hair removal result for each skin phototype. Results: Analyzing the percentage of satisfaction after LED photoepilation, satisfaction grade 3 and 4 represent approximately 95% of the participants. Surprisingly, there was no statistical correlation between the increase in skin phototype and the number of sessions needed to achieve the complete photoepilation effect. Unlike laser technology, which usually requires a high number of sessions for higher phototypes. No correlation with age was also reported. Conclusion: We can conclude that high power LED technology with effective tip cooling was able to achieve highly efficient results for 95.7% of treated patients, without the need to increase the number of sessions for phototypes 4 to 6.

Rationale for Parameters of Energy-Saving Illumination inside Agricultural Premises and Method of Its Values Calculation

High-quality lighting of premises in the cultivation of farm animals is an important condition for the successful development of the agro-industrial complex. Sufficient lighting with the simulation of sunrise and sunset which increases daylight hours to 15–16 h can raise the level of production by 8–15%. The most innovative, economical and efficient light source for livestock, poultry and greenhouse buildings are LED lamps allowing for a short payback period. The difference between the models developed by the authors and the traditional point method is taking into account lamp length o, lamp suspension height, location of the illuminated area under the lamp at displacement and observation angles, and luminous flux of light source, and the most important thing is body angle of the light source. This paper presents the method for calculating illumination under the LED lamp due to the large error in the values obtained by theoretical methods due to the lack of a correction factor for changing the illumination of the lamp (0.8). Prediction of crystal heating was carried out by verification calculation in the ANSYS/CFX software package. Forecasting the illumination of the fodder table was carried out by calculation in the DIALux evo software package. The main parameters of an energy-saving LED lamp (power consumption, luminous flux, color temperature and color) were selected. The consumption of electrical energy decreased by 85%; the average level of illumination increased and amounted to 123.1 lux. The developed method for calculating the illumination under the LED lamp can be considered satisfactory, the Student and Fisher criteria do not exceed tabular values and the correlation coefficient showed a close relationship. To comply with electrical safety standards in the premises, a resonant power supply system for LED lamps is offered.

Structured illumination microscopy based on principal component analysis

Structured illumination microscopy (SIM) is one of the powerful super-resolution modalities in bioscience with the advantages of full-field imaging and high photon efficiency. However, artifact-free super-resolution image reconstruction requires precise knowledge about the illumination parameters. The sample- and environment-dependent on-the-fly experimental parameters need to be retrieved a posteriori from the acquired data, posing a major challenge for real-time, long-term live-cell imaging, where low photobleaching, phototoxicity, and light dose are a must. In this work, we present an efficient and robust SIM algorithm based on principal component analysis (PCA-SIM). PCA-SIM is based on the observation that the ideal phasor matrix of a SIM pattern is of rank one, leading to the low complexity, precise identification of noninteger pixel wave vector and pattern phase while rejecting components that are unrelated to the parameter estimation. We demonstrate that PCA-SIM achieves non-iteratively fast, accurate (below 0.01-pixel wave vector and 0.1% of 2pi relative phase under typical noise level), and robust parameter estimation at low SNRs, which allows real-time super-resolution imaging of live cells in complicated experimental scenarios where other state-of-the-art methods inevitably fail. In particular, we provide the open-source MATLAB toolbox of our PCA-SIM algorithm and associated datasets. The combination of iteration-free reconstruction, robustness to noise, and limited computational complexity makes PCA-SIM a promising method for high-speed, long-term, artifact-free super-resolution imaging of live cells.

Effect of Duration of LED Lighting on Growth, Photosynthesis and Respiration in Lettuce.

Parameters of illumination including the spectra, intensity, and photoperiod play an important role in the cultivation of plants under greenhouse conditions, especially for vegetables such as lettuce. We previously showed that illumination by a combination of red, blue, and white LEDs with a high red light intensity, was optimal for lettuce cultivation; however, the effect of the photoperiod on lettuce cultivation was not investigated. In the current work, we investigated the influence of photoperiod on production (total biomass and dry weight) and parameters of photosynthesis, respiration rate, and relative chlorophyll content in lettuce plants. A 16 h (light):8 h (dark) illumination regime was used as the control. In this work, we investigated the effect of photoperiod on total biomass and dry weight production in lettuce plants as well as on photosynthesis, respiration rate and chlorophyll content. A lighting regime 16:8 h (light:dark) was used as control. A shorter photoperiod (8 h) decreased total biomass and dry weight in lettuce, and this effect was related to the suppression of the linear electron flow caused by the decreasing content of chlorophylls and, therefore, light absorption. A longer photoperiod (24 h) increased the total biomass and dry weight, nevertheless an increase in photosynthetic processes, light absorption by leaves and chlorophyll content was not recorded, nor were differences in respiration rate, thus indicating that changes in photosynthesis and respiration are not necessary conditions for stimulating plant production. A simple model to predict plant production was also developed to address the question of whether increasing the duration of illumination stimulates plant production without inducing changes in photosynthesis and respiration. Our results indicate that increasing the duration of illumination can stimulate dry weight accumulation and that this effect can also be induced using the equal total light integrals for day (i.e., this stimulation can be also caused by increasing the light period while decreasing light intensity). Increasing the duration of illumination is therefore an effective approach to stimulating lettuce production under artificial lighting.

Self-Sustained Euler Buckling of an Optically Responsive Rod with Different Boundary Constraints

Self-sustained oscillations can directly absorb energy from the constant environment to maintain its periodic motion by self-regulating. As a classical mechanical instability phenomenon, the Euler compression rod can rapidly release elastic strain energy and undergo large displacement during buckling. In addition, its boundary configuration is usually easy to be modulated. In this paper, we develop a self-sustained Euler buckling system based on optically responsive liquid crystal elastomer (LCE) rod with different boundary constraints. The buckling of LCE rod results from the light-induced expansion and compressive force, and the self-buckling is maintained by the energy competition between the damping dissipation and the net work done by the effective elastic force. Based on the dynamic LCE model, the governing equations for dynamic Euler buckling of the LCE rod is formulated, and the approximate admissible trigonometric functions and Runge-Kutta method are used to solve the dynamic Euler buckling. Under different illumination parameters, there exists two motion modes of the Euler rod: the static mode and the self-buckling mode, including alternating and unilateral self-buckling modes. The triggering conditions, frequency, and amplitude of the self-sustained Euler buckling can be modulated by several system parameters and boundary constraints. Results indicate that strengthening the boundary constraint can increase the frequency and reduce the amplitude. It is anticipated that this system may open new avenues for energy harvesters, signal sensors, mechano-logistic devices, and autonomous robots.

Motion-resistant structured illumination microscopy based on principal component analysis.

Structured illumination microscopy (SIM) has become one of the most significant super-resolution techniques in bioscience for observing live-cell dynamics, thanks to fast full-field imaging and low photodamage. However, artifact-free SIM super-resolution reconstruction requires precise knowledge about variable environment-sensitive illumination parameters. Conventional algorithms typically, under the premise of known and reliable constant phase shifts, compensate for residual parameters, which will be easily broken by motion factors such as environment and medium perturbations, and sample offsets. In this Letter, we propose a robust motion-resistant SIM algorithm based on principal component analysis (mrPCA-SIM), which can efficiently compensate for nonuniform pixel shifts and phase errors in each raw illumination image. Experiments demonstrate that mrPCA-SIM achieves more robust imaging quality in complex, unstable conditions compared with conventional methods, promising a more compatible and flexible imaging tool for live cells.

Considerations for the Use of Photobiomodulation in the Treatment of Retinal Diseases.

Photobiomodulation (PBM) refers to the beneficial effect produced from low-energy light irradiation on target cells or tissues. Increasing evidence in the literature suggests that PBM plays a positive role in the treatment of retinal diseases. However, there is great variation in the light sources and illumination parameters used in different studies, resulting in significantly different conclusions regarding PBM's therapeutic effects. In addition, the mechanism by which PBM improves retinal function has not been fully elucidated. In this study, we conducted a narrative review of the published literature on PBM for treating retinal diseases and summarized the key illumination parameters used in PBM. Furthermore, we explored the potential molecular mechanisms of PBM at the retinal cellular level with the goal of providing evidence for the improved utilization of PBM in the treatment of retinal diseases.

Effect of Na doping and heat treatment on the characteristics of ZnO thin films and ZnO/Si cells

• Undoped and Na doped ZnO films and ZnO/Si cells fabricated by chemical spray pyrolysis. • Band gap energy and resistivity of ZnO thin films decreased with Na doping and thermal annealing. • Power conversion efficiency of ZnO/Si heterojunction cell remarkably increased with Na doping and thermal annealing. Undoped and sodium doped ZnO thin films were grown on glass and Si substrates by spray pyrolysis. Post thermal annealing was applied for 1 h at 350 °C. Effect of Na doping and thermal annealing on the properties of ZnO thin films were investigated via XRD, UV–Visible spectrometry and resistivity measurements. Resistivity of the Na doped and annealed ZnO film was decreased to 7.15x10 3 Ω.cm from 3.26x10 4 Ω.cm where band gap energy was decreased to 3.31 eV from 3.36 eV. Current-voltage measurements held for all ZnO/Si heterostructures in dark and under illumination and device parameters were determined. Again best result obtained for the device in which both Na doping and annealing were applied as efficiency was increased to 4.57% from 2.01%.

Low-cost programable stroboscopic illumination with sub-microsecond pulses for high-throughput microfluidic applications

To visualize fast-moving objects in microfluidic applications, the image acquisition time must be on the order of a microsecond or less. Commercial imaging systems capable of such short exposure times may be too expensive for many research laboratories. We have therefore developed a low-cost stroboscopic illumination for transmitted-light microscopy based on a high-power LED that can be coupled to a standard industrial camera and provides exposure times on the order of 500 ns. The system is designed to be easily mounted on a standard condenser of an inverted microscope. The illumination is controlled by a fast Arduino-compatible Teensy® 4.0 development board, and the illumination parameters can be set from a PC via a graphical user interface written in Python. The system has been successfully used for high-throughput cell phenotyping using deformability cytometry on a Nikon TE2000 microscope, as well as for droplet microfluidic on an old Olympus inverted microscope.

Robust U‐Net: Development of robust image enhancement model using modified U‐Net architecture

SummaryThe image dehazing stage is used significantly as a preprocessing step for various applications such as remote sensing and long range imaging and automatic driver assistance system. Images acquired under low illumination, fog and snow conditions frequently show qualities like low contrast and low brightness, which genuinely influence the enhanced abstract visualization on natural eyes and extraordinarily limit the exhibition of different machine vision frameworks. The images that are captured in low‐light or heavy fog might have salient features that cannot be extracted using standard computer vision systems. A good way to get the enhanced image is to determine the transmission map (haze density or low illumination parameters) of air‐light media from each pixel of the input image. In this article, an improved U‐Net architecture is proposed to enhance images and provide robust performance metrics against the existing methods. In this model, the pooling operations in generalized U‐Net architecture are replaced by discrete wavelet transform based on up and down samplings. An attention module is developed by fusing both up and down samples to identify the missing information of low‐level features in up‐samples. The proposed architecture for U‐Net tested with different datasets: See‐in‐the‐Dark (SID) dataset, Exclusively Dark Image Dataset (ExDark), Realistic Single Image Dehazing (RESIDE) dataset, and few real‐time images and achieves superior performance metrics in terms of PSNR, MSE, and SSI when compared to the other state‐of‐art methods.

Study about photoinduction-based technology for trapping small brown planthopper

To provide a theory to guide the selection of the illumination parameters of light emitting diode (LED)-based light sources used for trapping Laodelphax striatellus, we used LED light sources and devices built in-house to detect L. striatellus phototactic behavior. Through phototaxis screening experiments of different light sources and the comparative experimental method, we analyzed the response patterns of L. striatellus to wavelength, light intensity, layout, flash frequency of monochromatic light sources, as well as combined color light sources, and discussed the mechanisms of the phototactic behavior of L. striatellus under different light sources. The results of the monochromatic light experiment showed that the trapping rate of the L. striatellus to the linear blue light source of 460 nm was the highest and was also significantly affected by the light intensity. The results of the experiments with the combined color light sources showed that compared with the linear 460 nm blue light source, the trapping rate of the L. striatellus was significantly improved by the polychromatic light, and the blue–green light led to the best improvement, reaching 1.5 times that of the trapping rate in the case of monochromatic light sources. The wavelength composition, light intensity, shape, and flash frequency of the light source used in this study can provide a theoretical basis for the development of LED-based light traps specifically for L. striatellus.

Automated Wheat Diseases Classification Framework Using Advanced Machine Learning Technique

Around the world, agriculture is one of the important sectors of human life in terms of food, business, and employment opportunities. In the farming field, wheat is the most farmed crop but every year, its ultimate production is badly influenced by various diseases. On the other hand, early and precise recognition of wheat plant diseases can decrease damage, resulting in a greater yield. Researchers have used conventional and Machine Learning (ML)-based techniques for crop disease recognition and classification. However, these techniques are inaccurate and time-consuming due to the unavailability of quality data, inefficient preprocessing techniques, and the existing selection criteria of an efficient model. Therefore, a smart and intelligent system is needed which can accurately identify crop diseases. In this paper, we proposed an efficient ML-based framework for various kinds of wheat disease recognition and classification to automatically identify the brown- and yellow-rusted diseases in wheat crops. Our method consists of multiple steps. Firstly, the dataset is collected from different fields in Pakistan with consideration of the illumination and orientation parameters of the capturing device. Secondly, to accurately preprocess the data, specific segmentation and resizing methods are used to make differences between healthy and affected areas. In the end, ML models are trained on the preprocessed data. Furthermore, for comparative analysis of models, various performance metrics including overall accuracy, precision, recall, and F1-score are calculated. As a result, it has been observed that the proposed framework has achieved 99.8% highest accuracy over the existing ML techniques.

СВЕТОВОЕ АНТРОПОГЕННОЕ ЗАГРЯЗНЕНИЕ: ДЕЙСТВИЕ НА НАСЕКОМЫХ

The amounts and diversity of insects make them significant contributors to ecosystems stability. Human activities are associated with rapid changes in the lighting conditions of ecosystems. These changes produce diverse alterations to behavior, physiology and, ultimately, population sizes of insects. The present review addresses the changes in insects that occurre upon anthropogenic light pollution. The insects that are active in nighttime are subject to direct negative impacts of light at night primarily because it shortens the foraging and proliferation periods and thus diminishes insect populations, whereas daytime species may benefit somehow due to the lengthening of the periods of their activity. The physiological state that allows insects to survive during winter, the diapause, critically depends on daytime duration; therefore, longer periods of illumination may result in a delayed or incomplete diapause in both daytime and nighttime insects. Migratory insects are subject to changes in focal light sources, because such changes may interfere with migration routes and thus lead to massive losses of insects. Indirect light pollution cases are associated with the use of light polarizing materials, such as asphalts pavements and polymeric films, which distort insects’ abilities to use light polarization for detecting of water surfaces. Although the almost ubiquitous light pollution is a relatively recent phenomenon, some insect species have already developed adaptations to it. However, the impact of light pollution on insects is still poorly studied not only because of their enormous diversity but also because of rapidly changing characteristics of artificial light sources, such as their luminosity and spectra. Proper choices of illumination parameters may not only ameliorate the negative impact of light at night on insects but also may help to develop illumination means of control of pests and synanthropic insects.

The Optical Design of a LED-Reflector Module in Road Illumination

In recent years, there has been a trend towards energy-efficient, long-lasting, environmentally friendly, and technology-compatible LED road luminaires. In this study, the optical design and analysis of the LED road luminaire model for the M1 and M2 illumination classes roads, which are the roads with the highest importance, have been carried out. In the research, the unique reflector design was made using SolidWorks 3D design software. XLamp CXA1520 LED light source by Cree company was preferred during the design. 21 LEDs were placed on the reflector at the ideal distance and LED luminaire model was created in LightTools illumination design software. A simulation study was performed for the LED luminaire model created on LightTools software and the distribution curve of luminous intensity was obtained. At the same time, the EULUMDAT (.ldt) file, which is required for road illumination analysis, was produced with LightTools software. The obtained .ldt file was transferred to DIALux illumination calculation program and simulated for M1 and M2 class roads. Illumination parameters obtained from DIALux analysis have been optimized by comparing them with the road illumination criteria accepted by International Commission on Illumination (CIE). It has been observed that the designed LED luminaire model significantly meets the M1 and M2 class road illumination criteria defined by CIE. In the study, it was also discussed what changes can be made in the optical material to meet all criteria.

The effects of lamp types and surface reflectance combinations on the subjective perception of a simulated lit hospital ward environment

PurposeGood illumination creates an aesthetic environment that may positively influence patients’ well-being and provide comfort to the hospital staff. This study aims to focus on exploring the energy efficiency of lighting and subjective perception of the lit environment in a hospital ward to assess quality indicators of ambient lighting conditions.Design/methodology/approachThe existing conventional tubular fluorescent lamp–based lighting system in the surveyed patients’ ward was retrofitted with light-emitting diode (LED) luminaires to explore illumination and energy parameters. Thereafter, a software lighting model was created, simulated and analyzed. A Web-based survey with five bipolar adjective pairs in a semantic differential scale was conducted with 48 participants to record and analyze their subjective responses pertaining to the variations in lamp types and surface reflectance combinations.FindingsThe findings imply that the LED tubular lamp–based illumination was deemed more adequate compared to other lamp types and the effects of variations in room surface reflectance combinations on the participants’ responses were statistically significant at α = 0.05 level. The simulated horizontal work plane average illuminance level varied from 131 to 171 lx, mean room surface exitance (MRSE) levels remained between 30 and 90 lm/m2 and overall uniformity of illuminance remained between 0.5 and 0.7.Originality/valueIn a hospital ward illuminated by LED tubular lamps, variations in room surface reflectance combinations for a constant luminous flux package output from the lamps may affect the subjective perception of users and the correlation between horizontal work plane average illuminance and MRSE is found to be highly linear (coefficient of determination > 0.97).

Localization-assisted stimulated Brillouin scattering spectroscopy.

Brillouin spectroscopy has emerged as a promising modality to noninvasively probe the mechanical properties of biologically relevant materials. Stimulated Brillouin scattering (SBS) has the potential to improve measurement speed and resolution by exploiting a resonant amplification of the scattered signal, yet current SBS spectrometers have not provided significant improvements due to fundamental and practical limitations of illumination and detection parameters. To overcome this challenge, here we derive a signal localization theory for the Brillouin spectral domain and accordingly design an SBS spectrometer with much improved performances compared to state-of-the-art systems. We present experimental and simulated data validating our theory, which result in a tenfold improvement in acquisition speed, or an order of magnitude improved spectral precision, for SBS spectral measurements when properly optimizing the SBS photon detection architecture.

The Effect of Dynamic Lighting for Working Shift People on Clinical Heart Rate Variability and Human Slow Wave Sleep

The quality of sleep during lunch breaks will affect the work efficiency, concentration, and mood of workers, and then increase the performance of workers. In this study, Dynamic CCT lighting is proposed as a method to control sleep quality, and a novel hypnotic lighting system is developed according to the experimental design. Pulse width modulation(PWM) is used for controlling sleep lights and adjusting and controlling the spectrum intensity of polychromatic LED to realize the color mixing, which conforms to CCT, illumination, uniformity, and other parameters in the experimental design. The control group of this study is in a dark room, and the experimental group is given dim light and Dynamic CCT lighting. Through volunteer psychological questionnaire evaluation, objective Sleep Wrist Actigraphy and Heart Rate Variability (HRV) are used analyzing sleep quality and Autonomic Nervous System (ANS). The result is found that the sleep environment with Dynamic CCT lighting is better than that with Dim light in three kinds of sleep lighting environments, while the sleep environment of Dynamic CCT lighting is very similar to that of a dark room. In terms of work efficiency after sleep, Dynamic CCT used in the sleep environment of lighting and Dim light is significantly better than that in a dark room.

Robust Fourier ptychographic microscopy via a physics-based defocusing strategy for calibrating angle-varied LED illumination.

Fourier ptychographic microscopy (FPM) is a recently developed computational imaging technique for wide-field, high-resolution microscopy with a high space-bandwidth product. It integrates the concepts of synthetic aperture and phase retrieval to surpass the resolution limit imposed by the employed objective lens. In the FPM framework, the position of each sub-spectrum needs to be accurately known to ensure the success of the phase retrieval process. Different from the conventional methods with mechanical adjustment or data-driven optimization strategies, here we report a physics-based defocusing strategy for correcting large-scale positional deviation of the LED illumination in FPM. Based on a subpixel image registration process with a defocused object, we can directly infer the illumination parameters including the lateral offsets of the light source, the in-plane rotation angle of the LED array, and the distance between the sample and the LED board. The feasibility and effectiveness of our method are validated with both simulations and experiments. We show that the reported strategy can obtain high-quality reconstructions of both the complex object and pupil function even the LED array is randomly placed under the sample with both unknown lateral offsets and rotations. As such, it enables the development of robust FPM systems by reducing the requirements on fine mechanical adjustment and data-driven correction in the construction process.