Single Lens Research Articles

An automated approach to the alignment of compound refractive lenses.

Compound refractive lenses (CRLs) are established X-ray focusing optics, and are used to focus the beam or image the sample in many beamlines at X-ray facilities. While CRLs are quite established, the stack of single lens elements affords a very small numerical aperture because of the thick lens profile, making them far more difficult to align than classical optical lenses that obey the thin-lens approximation. This means that the alignment must be very precise and is highly sensitive to changes to the incident beam, often requiring regular readjustments. Some groups circumvent the full realignment procedure by using engineering controls (e.g. mounting optics) that sacrifice some of the beam's focusing precision, i.e. spot size, or resolution. While these choices minimize setup time, there are clear disadvantages. This work presents a new automated approach to align CRLs using a simple alignment apparatus that is easy to adapt and install at different types of X-ray experiments or facilities. This approach builds on recent CRL modeling efforts, using an approach based on the Stochastic Nelder-Mead (SNM) simplex method. This method is outlined and its efficacy is demonstrated with numerical simulation that is tested in real experiments conducted at the Advanced Photon Source to confirm its performance with a synchrotron beam. This work provides an opportunity to automate key instrumentation at X-ray facilities.

Anatomy of the geometric phase for an optical vortex transiting a lens

We present an analytical means of quantifying the fractional accumulation of the geometric phase for an optical vortex transiting a cylindrical lens. The standard fiber bundle of a sphere of modes is endowed with a supplementary product space at each point so that the beam waists and their positions can be explicitly tracked as functions of lens transit fraction. The method is applied to quantify the accumulation of the geometric phase across a single lens as a function of initial state and lens position within the beam. It can be readily applied to a series of lenses as well.

Portrait imaging relighting system based on a simplified photometric stereo method.

This study proposes a portrait image relighting system based on a simplified photometric stereo method. The system, comprising a controllable digital single lens reflex camera and five polarized flashlights, can obtain a color shade-less image and synthesize a normal map from shaded images. When calibrating the photometric stereo, the normal map is taken as a linear combination of shaded images and clamped with respect to specific normal directions on a white-coated sphere. The relit images were generated through inverse rendering in a predefined virtual environment. To evaluate personal preference, 24 adult subjects were recruited to conduct subjective assessments comparing the deep portrait relighting method results. From experiments regarding different scenarios, we concluded that the proposed system based on a simplified photometric stereo performs acceptably for relighting portrait images.

Chromatic aberration correction in bi-focal augmented reality display by the multi-layer Pancharatnam-Berry phase lens.

Chromatic aberration is a main obstacle for the commercial application of augmented reality displays. The current digital and optical compensation methods of reducing the chromatic aberration suffer from processing time, power consumption or complex design. Here, a simple strategy of chromatic aberration correction in bi-focal augmented reality near-eye display based on multi-layer Pancharatnam-Berry phase lens has been demonstrated and verified by experimental results. The multi-layer Pancharatnam-Berry phase lens, as a part of optical combiner, is fabricated by three liquid crystal polymer phase lenses with central wavelength in red, green, and blue, respectively. The multi-layer Pancharatnam-Berry phase lens can effectively reduce the chromatic aberration in both convex and concave mode of bi-focal augmented reality system, where the color breakup of virtual images captured in bi-focal augmented reality display is significantly alleviated. Comparing to the value of ΔK = 1.3 m-1 in single green Pancharatnam-Berry phase lens, the multi-layer Pancharatnam-Berry phase lens system significantly reduce the ΔK to 0.45 m-1 with reduction of 65.4%, which finally decreases the longitudinal chromatic aberration and improve the quality of images. The proposed broadband multi-layer Pancharatnam-Berry phase lens can benefit augmented reality displays and find widespread application in the near-eye displays.

Pupil apodization in digital holographic microscopy for reduction of coherent imaging effects

A dark-field Digital Holographic Microscope with a single lens for imaging is a potential candidate for future overlay metrology on semiconductor wafers. Aberrations caused by this single lens are computationally corrected allowing high-resolution imaging over a large wavelength range. However, the spatially-coherent imaging conditions in our microscope introduce coherent imaging artifacts that can limit the metrology performance. We present computational apodization of the optical field in the exit pupil of the lens as a potentially effective solution to mitigate these coherent imaging effects. A comparison of experimental data and simulations is presented that demonstrates the importance of this apodization in metrology applications. Moreover, our data also shows that exploiting the full potential of DHM requires an imaging lens with low optical scattering levels.

Overcoming the error of optical power measurement caused by the curvature radius.

In traditional focimeter measurements, the lens cannot completely coincide with the diaphragm owing to the change of radius, resulting in an increase in the power measurement error with an increase in the lens power. We proposed a method, using the SVM machine learning algorithm, to restore the measurement of the focimeter, using a lens power data set obtained from lens features, obtained through an automatic acquisition system. Total up to 83 groups of single focus lenses with refractive indices of 1.56 and 1.60, ranging from -10 m-1 to + 8 m-1 every 0.25 m-1 and -10.5 m-1 to -15 m-1 every 0.5 m-1, were used for lens image acquisition. The experimental results show that the ten-fold average F1 score of the classification under this method is 100%. The test lens power can be accurately identified and the measurement error can be overcome.

A concentrated sunlight energy wireless transmission system for space solar energy harvest

Advancements in spacecraft formation and space solar power plant technologies promote wireless energy transmission among satellites and the Earth. Although microwave-based, laser-based, and sunlight-based wireless energy transmission technologies have been reported previously, none of them have been practically deployed because of major limitations. In this paper, a concentrated sunlight energy wireless transmission system (CSEWTS) using single plano-convex lenses to harvest space sunlight and a single corresponding optical fibre bundle (OFB) to realize flexible energy transmission is schematically developed and its prototype is established experimentally. This system utilizes sunlight as the transmission media to avoid intermediate energy conversion and where energy efficiency can be enhanced compared to microwave-based or laser-based energy wireless transmission. Furthermore, the OFB-based CSEWTS can lighten the mirror-based system, which was developed previously. Various effects of optical coupling, condenser outline in the energy receiver, smog, distance, and bending were experimentally or theoretically investigated. An optimized coupling incident angle into OFB of 18° was attained theoretically and validated experimentally where an improvement of 19.9% in system efficiency was acquired from a wrong angle to an optimal one. Besides, aspheric lenses were experimentally proved to be more appropriate to condense sunlight where a 16.5% − 19.5% enhancement was obtained. In addition, lens coating, condenser outline in the energy receiver, smog, and distance effects were also analyzed. Smog harms energy transmission which casts shadows on its space-Earth application. Energy transmission to a no-cloud area is the only probable option. The developed technologies can also be used in solar sail spacecraft, contributing to global carbon neutrality and clean aerospace flight.

A Randomized Comparative Study on Effectiveness of Combination of Spectacles with Atropine 0.01% on Myopia Progression in Teenage

Myopia (nearsightedness) is the most common cause of visual impairment globally. Prevalence of myopia varies among geographical regions, ethnic populations, and age groups. This study is aimed to investigate whether combination of spectacles with atropine 0.01% treatment reduce myopia progression in teenage and to compare interventions (bifocal + atropine 0.01%, single vision lens + atropine 0.01%) of interest with each other, and to single vision lens control group. Children of edge 8-15 years in group were randomly assigned to one of three treatments; single vision lens, single vision lens + atropine 0.01%, and bifocal + atropine 0.01%. Myopia progression was assessed using streak retinoscope following cycloplegia over a period of 1 year. Treatment effect of both interventions were found statistically insignificant (p value>0.05%). Over a period of 1 year both single vision lens + atropine 0.01% and bifocal + atropine 0.01% were found to be insignificant as compared to single vision control group.

Trends in myopia management attitudes and strategies in clinical practice: Survey of eye care practitioners in Africa

PurposeThere remains a lack of information on the perception and adoption of myopia control strategies among African eye care practitioners (ECPs). This study provides an African perspective to similar previous studies conducted in other parts of the world. MethodsA self-administered survey in English and French was distributed to ECPs across Africa. The items on the questionnaire assessed their level of concern about the increasing prevalence of paediatric myopia, perceived efficacy, opinions on, and adoption of various myopia management modalities. ResultsResponses were obtained from 330 ECPs working in 23 African countries. Respondents were highly concerned about the increasing prevalence of paediatric myopia in their clinic (median 8/10) and perceived approved myopia control soft contact lenses as the most effective at slowing myopia progression (mean perceived reduction in myopia progression ± SD; 53.9 ± 27.1%), followed by single vision spectacles (53.1 ± 30.9%), and orthokeratology (52.8 ± 28.0%). Multifocal soft contact lenses (40.4 ± 25.8%) and pharmaceutical agents such as topical atropine drops (39.5 ± 27.1%) were perceived as least effective in slowing myopia progression. Although ECPs reported being aware of various myopia control strategies, they still mainly prescribed single vision spectacles to a large proportion (64.3 ± 29.9%) of young progressing myopes. Nearly one-third (27%) of ECPs who prescribed single vision lenses stated they were concerned about the cost implications to patients. Other reported concerns included safety of, and inadequate information about myopia control options. ConclusionsAfrican ECPs continue to prescribe single vision lenses for progressing myopes despite being aware of the various myopia control options. Practitioners’ perceptions of the efficacy of several modalities to slow myopia progression do not align with the current best evidence. Clear practice guidelines and continuing education on myopia control are warranted to inform and guide the management of myopic patients in Africa.

Overview on Defocus Incorporated Multiple Segments Lenses: A Novel Perspective in Myopia Progression Management

Myopia is becoming more common across the world, affecting approximately two billion people and rising. Different kinds of therapies (optical, pharmaceutical, environmental, or behavioral) have been proposed to decrease myopia progression, but with variable results and a lack of standardization. The evidence that targeted myopic defocus inhibits eye length growth has paved the way for several contact and spectacle lense designs to induce a peripheral defocus, thus slowing myopia progression, but the perfect configuration has yet to be defined. One of the newest and more promising approaches in this field is the use of Defocus Incorporated Multiple Segments (DIMS) lenses. These lenses are built from the assumption that targeted myopic defocus, produced by 396 mid-peripheral lenslets with positive power, inhibits eye length growth. Recent studies have highlighted the effectiveness of these lenses compared to children who had worn single vision spectacle lenses, in terms of myopia control and tolerability. Despite the evidence that these lenses can help slow down the progression of myopia, the occasional mid-peripheral aberrations they can induce, as well as the overall eye strain that comes with wearing them, should not be overlooked. The aim of this review is to give attention to the advantages and the shortfalls of this new approach and to evaluate its effectiveness in clinical practice.

Short-term delay in neural response with multifocal contact lens might start at the retinal level.

Multifocal simultaneous imaging challenges the visual system to process the multiple overlaps of focused and defocused images. Retinal image processing may be an important step in neuroadaptation to multifocal optical images. Our aims are, firstly to evaluate the short-term effect of different multifocal contact lenses (MF) on retinal activity in young healthy subjects (Experiment#1) and secondly, to evaluate any changes in retinal activity in presbyopic patients fitted with MF over a 15-day period (Experiment#2). In Experiment-#1, 10 emmetropic healthy young subjects were included to evaluate the short-term effect of different MFs designs. In Experiment #2, 4 presbyopic subjects were included to wear MF for 15days. Following the ISCEV Standards, multifocal electroretinograms (mfERGs) were recorded to evaluate different retinal regions under different conditions: with single vision contact lens (SVCL) and with center-distance and center-near MF. In Exp#1 the peak time of N1, P1 and N2 were found to be delayed with the MF (p ≤ 0.040). There was a significant reduction for N1 amplitude in all retinal regions (p < 0.001), while for P1 and N2 amplitudes this reduction was more significant in the peripheral regions (p < 0.005, ring 5 to 6). With center-near MF the mean response density (nV/deg2) showed a significant decrease in all wave components of the mfERGs response, particularly from Ring 3 to Ring 6 (p < 0.001, all Rings). In Exp#2, the mean mfERG response is similar between SVCL and center-distance MF, while center-near MF showed an increase in implicit time N1 and P1 on day 1 that tends to recover to baseline values after 15days of MF wear. significant changes in the mfERGs responses were found with the MF lens, being most noticeable with the center-near MF lens design. The present results suggest that the observed delay in cortical response described during the adaptation to multifocality may partially begin at the retina level.

Human-Computer Interaction with Detection of Speaker Emotions Using Convolution Neural Networks.

Emotions play an essential role in human relationships, and many real-time applications rely on interpreting the speaker's emotion from their words. Speech emotion recognition (SER) modules aid human-computer interface (HCI) applications, but they are challenging to implement because of the lack of balanced data for training and clarity about which features are sufficient for categorization. This research discusses the impact of the classification approach, identifying the most appropriate combination of features and data augmentation on speech emotion detection accuracy. Selection of the correct combination of handcrafted features with the classifier plays an integral part in reducing computation complexity. The suggested classification model, a 1D convolutional neural network (1D CNN), outperforms traditional machine learning approaches in classification. Unlike most earlier studies, which examined emotions primarily through a single language lens, our analysis looks at numerous language data sets. With the most discriminating features and data augmentation, our technique achieves 97.09%, 96.44%, and 83.33% accuracy for the BAVED, ANAD, and SAVEE data sets, respectively.

Visual outcome of single piece yellow tinted hydrophobic acrylic intraocular lens: A hospital based prospective observational study

To evaluate the visual outcome of single piece yellow tinted hydrophobic acrylic intraocular lens (IOL) following phacoemulsification.A single center, hospital based, prospective, observational study. Eligible patients with significant cataract, underwent phacoemulsification with implantation of single piece yellow tinted hydrophobic acrylic IOL. Patients followed up for 6 months. Pre and post-operative assessment of UDVA, CDVA was done and documented in LogMAR values. Contrast sensitivity by Pelli-Robson chart, refraction by Auto refractometer was evaluated pre and post operatively. Post-operative evaluation of glistening and PCO done by slit lamp examination. Glare evaluated by pen-torch contrast sensitivity method. Adverse events documented on regular follow-up.132 patients were enrolled in the study. Majority of the subjects (97.7%) achieved expected visual outcome of LogMAR 0.0-0.2 on final follow-up day. Statistically significant improvement in contrast sensitivity noted in 99.2% of our patients. The mean refractive spherical equivalent at 180 days was 0.10±0.81. The incidence of glistening was 3.8% at 180 days follow up. Glare was present in 4.6% subjects on first operative day, 3% on 3rd and decreased to 0.8% on 7th postoperative day. None of our patients complained of glare after 1 month. The incidence of PCO and adverse events was 0.8% and 15.2% respectively, on last postoperative follow-up.Implantation of single piece yellow tinted hydrophobic acrylic IOL provides expected visual outcome, refractive stability, enhances contrast sensitivity with minimal glistening, glare and adverse events. The square edge design of the hydrophobic lens reduces incidence of posterior capsular opacification.

The effect of concentric and aspheric multifocal soft contact lenses on binocular vision in young adult myopes

PurposeMultifocal soft contact lenses (MFCLs) are prescribed to inhibit myopia progression; these include aspheric and concentric designs. The effects of MFCLs on visual quality, accommodation and vergence in young-adult myopes were evaluated. MethodsParticipants were twenty-six myopes (19–25 years, spherical equivalent −0.50 to −5.75D), with normal binocular vision and no past myopia control. Pupil sizes were 4.4 ± 0.9 mm during distance viewing and 3.7 ± 0.8 mm at near. In random order, participants wore four MFCLs: Proclear single vision distance, MiSight concentric dual focus (+2.00D), distance center aspheric (Biofinity, +2.50D) (CooperVision lenses), and NaturalVue aspheric (Visioneering Technologies). Testing included visual acuity, contrast sensitivity (Pelli-Robson), stereoacuity, accommodation response, negative and positive relative accommodation, horizontal phorias, horizontal fusional vergence and AC/A ratio, and a visual quality questionnaire. ResultsThe four lenses differed in distance (p = 0.001) and near visual acuity (p = 0.011), and contrast sensitivity (p = 0.001). Compared with the single vision lens, the Biofinity aspheric had the greatest visual impact: 0.19 ± 0.14 logMAR distance acuity reduction, 0.22 ± 0.15 log contrast sensitivity reduction. Near acuity was affected less than distance acuity; the reduction was greatest with the NaturalVue (0.05 ± 0.07 logMAR reduction). The MFCLs altered the autorefraction measure at distance and near (p = 0.001); the accommodation response was less with aspheric lenses. Negative relative accommodation reduced with the aspheric lenses (p = 0.001): by 0.9 ± 0.5D with Biofinity and 0.5 ± 0.7D with NaturalVue. Exophoric shifts were greater with aspheric lenses (1.8 ± 2.4Δ Biofinity, 1.7 ± 1.7Δ NaturalVue) than with the concentric MiSight (0.5 ± 1.3Δ). ConclusionsMFCLs alter visual performance, refraction and vergence; two aspheric lenses had greater effect than a concentric lens.

All-optical demonstration of a scalable super-resolved magnetic vortex core.

We first present the all-optical realization of a scalable super-resolved magnetic vortex core (MVC) by tightly focusing two modulated counter-propagating radially polarized doughnut Gaussian beams based on the vectoial diffraction theory and the inverse Faraday effect. It is shown that by imposing spiral phase plates (SPPs) on the incident vectorial beams, single three-dimensional (3D) super-resolved (λ3/22) MVC can be achieved in the 4π focusing setup, which is radically different from that produced with a single lens focusing. Furthermore, the light-induced MVC texture turns to be richer and more complex when the radially polarized beams are tailored by the SPPs and judiciously designed multi-ring filters all together. In this case, we are able to garner not only transverse super-resolved (0.447λ) MVC needle with an uniformly extended area (40λ) in the single lens focusing system, but also the multiple uniform 3D super-resolved (λ3/24) chain-like MVC cells in the 4π focusing system, thus giving rise to the tunable and scalable super-resolved MVC extension. The related physical mechanisms to trigger such peculiar magnetization polarization topologies are unraveled as well. These resultant achievements would pave the way for the integrated transfer and storage of optomagnetic information, atomic trapping, and beyond.

High Precision Visual Dimension Measurement Method with Large Range Based on Multi-Prism and M-Array Coding.

The visual dimension measurement method based on non-splicing single lens has the contradiction between accuracy and range of measurement, which cannot be considered simultaneously. In this paper, a multi-camera cooperative measurement method without mechanical motion is proposed for the dimension measurement of thin slice workpiece. After the calibration of the multi-camera imaging system is achieved through a simple and efficient scheme, the high-precision dimension measurement with a large field of view can be completed through a single exposure. First, the images of the edges of the workpiece are compressed and combined by splitting and merging light through the multi-prism system, and the results are distributed to multiple cameras by changing the light path. Then, the mapping relationship between the global measurement coordinates and the image coordinates of each camera is established based on the globally unique M-array coding, and the image distortion is corrected by the coding unit composed of black and white blocks. Finally, the edge is located accurately by edge point detection at the sub-pixel level and curve fitting. The results of measuring a test workpiece with the dimension of 24 mm × 12 mm × 2 mm through a single exposure show that the repeated measurement accuracy can reach 0.2 µm and the absolute accuracy can reach 0.5 µm. Compared with other methods, our method can achieve the large-field measurement through only one exposure and without the mechanical movement of cameras. The measurement precision is higher and the speed is faster.

Exploring the factors which impact overall satisfaction with single vision contact lenses

PurposeTo explore the impact of subjective factors (lens handling, comfort and vision) on overall single vision contact lens satisfaction. MethodsCorrelation analysis of a prospective, randomised, double-masked, bilateral crossover study involving 55 adapted lens wearers fitted with somofilcon A (SiHy) (clariti® 1 day, CooperVision) and etafilcon A (Hy) (1 DAY ACUVUE® MOIST, Johnson & Johnson Vision) was conducted. Subjective ratings of lens handling, comfort and vision collected after 1 week of lens wear for each lens type were correlated with overall satisfaction. Data were analysed by combining data for both lens types and also for each lens separately. ResultsFor the combined analysis, significant correlations (p < 0.01) were found between subjective ratings of overall satisfaction and ratings of handing for application (r = 0.64), handling for removal (r = 0.50), comfort upon application (r = 0.59), comfort at end of day (r = 0.61), overall satisfaction with comfort (r = 0.88) and overall satisfaction with vision (r = 0.64).Correlation analysis of the per lens data showed that lens specific correlations of overall satisfaction with handling for lens application varied greatly with lens material (SiHy: r = 0.26, p = 0.05 vs Hy: r = 0.72, p < 0.01). Correlation strength of comfort upon application/at end of day with overall satisfaction also varied with lens material (Application: SiHy: r = 0.40 vs Hy: r = 0.61; End of day: SiHy: r = 0.76 vs Hy: r = 0.58; all p ≤ 0.01). ConclusionOverall satisfaction was significantly correlated with the specific subjective evaluations of handling, vision and comfort. Correlations of overall satisfaction and ease of handling for each lens type suggest that, for habitual contact lens wearers, dissatisfaction with handling at the time of lens application can play a major role in overall dissatisfaction with a lens. Handling for application had a similar correlation (r) value as vision, suggesting that handling for application should not be underestimated when considering overall patient satisfaction.

Effects of Customized Progressive Addition Lenses vs. Single Vision Lenses on Myopia Progression in Children with Esophoria: A Randomized Clinical Trial.

Purpose To evaluate the effect of customized progressive addition lenses (CPALs) versus single vision lenses (SVLs) on the progression of juvenile-onset myopia in children with near esophoria. Methods Ninety-three Chinese children, aged 7–14 years with spherical equivalent refraction (SER) ranging from −0.50 to −4.00 D and near esophoria ≥2Δ, were randomly assigned into a CPALs (n = 46) and an SVLs group (n = 47) for a 2-year, double-masked, randomized trial. The primary outcome measure was the progression of myopia, as determined by cycloplegic autorefraction. A customized near addition, calculated by a regression equation, was prescribed to establish a fixed heterophoria status for each child, which was −3Δ exophoria. Results Eighty-four (90.3%) of the 93 children completed the 2-year follow-up. The mean initial near addition lenses were 1.65 ± 0.07 D (mean ± SE). The adjusted 2-year myopia progression was 0.23 ± 0.08 D slower in the CPALs group than in the SVLs group (p=0.046). Post hoc analysis found significantly larger treatment effects for CPALs in children without myopic parents (0.47 ± 0.15 D; 95% CI: 0.18–0.76), with lower baseline myopia (0.33 ± 0.09 D; 95% CI: 0.14–0.52; p < 0.05), with higher baseline accommodative lag (0.36 ± 0.11 D; 95% CI: 0.12–0.60; p < 0.05), and with higher baseline near esophoria (0.30 ± 0.10 D; 95% CI: 0.12–0.48; p < 0.05). Conclusion CPALs exerted a significant but minimal protective effect against myopia progression in Chinese children with esophoric myopia, as compared with SVLs. Regulating near heterophoria and accommodative lag by near addition lenses may not be an appropriate way to prevent myopia progression.

Compound-Specific Nitrogen Isotope Analysis of Amino Acids in Eye Lenses as a New Tool to Reconstruct the Geographic and Trophic Histories of Fish

Fish migration has always played an essential role in marine conservation and fisheries management. However, migration patterns are changing globally alongside changing ocean conditions. This affects the spatial scale of required governance and, consequently, our food supply. Technological advances in the bio-tracer approach using isotopes would make it possible to monitor fish migration differently from the conventional bio-logging method. Eye lenses of fish are incrementally grown and metabolically inert. Therefore, stable isotope analysis of eye lenses can reconstruct the geographic and trophic histories of fish. However, it is difficult to distinguish between the two pieces of information: migration and changing trophic relationships with the conventional bulk stable isotope approach. In this study, we measured the nitrogen isotope ratios of individual amino acids in eye lenses of chub mackerel (n = 3) from the western North Pacific to test whether the two pieces of information could be distinguished. A maximum of 34 growth layers was obtained from a single eye lens. For assigning the isotopic trends observed in lens tissues to specific life stages or size classes, we established a relationship between lens size and fork length (FL) as a reference framework. The reconstructed nitrogen isotope chorology of chub mackerel showed an increase in trophic position of about 1 unit from juvenile (FL ∼30 mm) to adult stages (FL ∼300 mm). The variation in nitrogen isotope ratios of phenylalanine (a source amino acid) in the eye lenses was –3 to 5‰. This baseline variability could be used for estimating fish movements. This study proposed compound-specific nitrogen isotope analysis of amino acids in eye lenses as a new tool capable of reconstructing the geographic and trophic histories of migratory fish.

Analisis Deformasi Jembatan Akibat Banjir Bandang Berbasis Fotogrametri Jarak Dekat

Monitoring the deformation of objects in the natural disaster area is one of the anticipative steps to reduce losses. In this case, this is an attempt to implement mitigation for the safety and viability of the community. Until this time, many constraint factors in the process of obtaining information regarding the strength of the structure and the changes of shape and dimension (per time unit) of the objects, one of which is the high operational cost and the duration of data processing while using a conventional measuring instrument. Through this article, a fast, cheap, easy, and accurate alternative method to detect deformation of the bridge material structure due to flash flood is only by using a Digital Single Lens Reflex (DSLR) camera. The bridge’s structures were photographed and processed with proprietary software to obtain the retro-reflective coordinate of the target that has been evenly attached to the bridge surface as a reference point. From a series of periodic photoshoots conducted from July 2020 to July 2021, deformation of the bridge structure was successfully detected with a magnitude between 0.026 mm – 5.867 mm with a measurement accuracy level was 0.081 mm. With this measurement accuracy level, this system is able to detect the deformation of structures smaller than 0.1 mm, and even invisible deformation can still be detected. This article will explain the technique and methodology of deformation measurement quickly and accurately only with a DSLR camera.