Individual Lenses Research Articles

TDCOSMO

Context. Time-delay cosmography is a technique for measuring H0 with strong gravitational lensing. It requires a correction for line-of-sight perturbations, and thus it is necessary to build tools to assess populations of these lines of sight efficiently. Aims. We demonstrate the techniques necessary to analyze line-of-sight effects at a population level, and investigate whether strong lenses fall in preferably overdense environments. Methods. We analyzed a set of 25 galaxy-galaxy lens lines of sight in the Strong Lensing Legacy Survey sample using standard techniques, then performed a hierarchical analysis to constrain the population-level parameters. We introduce a new statistical model for these posteriors that may provide insight into the underlying physics of the system. Reults. We find the median value of κext in the population model to be 0.033 ± 0.010. The median value of κext for the individual lens posteriors is 0.008 ± 0.015. Both approaches demostrate that our systems are drawn from an overdense sample. The different results from these two approaches show the importance of population models that do not multiply the effect of our priors.

A Spectacular Devonian Trilobite Specimen, Dalmanites pratteni, From Illinois Helps Shed Light on How Trilobite Eyes Worked

In 1912, the Field Museum purchased Henry Pratten's collection of fossils. One of the specimens was a dalmanitid trilobite with large eyes (Fig. 1) that Pratten collected from the Devil’s Backbone. In 1933, this specimen was described as a new species of trilobite, Dalmanites pratteni (P 16704) (Roy 1933). Delo (1935) described a new genus of trilobite, Dalmanitoides and assigned it to a new family, Synphorinae. He noted Dalmanites pratteni has similar ornamentation to this genus. Delo (1940) later places D. pratteni in the genus Odontochile. Other authors refer to it as Dalmanites pratteni (Clarkson and Levi-Setti 1975;Levi-Setti 1975; Frankie et al. 2008). Holloway and De Carvalho (2009) refer to it as ‘Dalmanites’ pratteni and state that this species “probably belongs to the Synphoriinae”. The stratigraphic position of this specimen was not recorded. Seid et al. (2009) published a detailed geologic map of the Devil’s Backbone. Most of the ridge is Middle Devonian Grand Tower and St. Laurent formations. However, the southern end of the ridge is faulted, and the Lower Devonian Backbone Limestone and Crystal Creek Chert (Emsian) is exposed. Frankie et al. (2008) and Devera et al. (2020) report Dalmanites pratteni occurring from the Crystal Creek Chert, indicating that the original specimen may have been collected here. One of the most remarkable features of this fossil is the record number of lenses for a Phacopida. Roy (1933) reports 42 rows of eyes, however: “The exact number of lenses cannot be determined, as not all of them are preserved, nor are the areas which they occupied distinctly outlined. It is, however, certain that there are not less than 770 lenses on each eye.” (Roy 1933). I used images of the eyes and illustration software to estimate the number of lenses by filling in the geometric pattern they exhibit. I counted 730 lenses on the right eye and 712 lenses on left eye, which is missing a sizable piece (Fig. 2). The structure of some individual lenses in this specimen can be seen due to differential weathering. Clarkson and Levi-Setti (1975) reported the large round lenses were composed of a doublet structure that followed the principles established by Descartes (1637) and Huygens (1690) to eliminate spherical distortion. This doublet structure allowed the lens to gather more light and focus it on a single point, and strongly indicates that these trilobites had better vision then previously established (Clarkson and Levi-Setti 1975).

ALMA follow-up of ∼ 3000 red-Herschel galaxies: The nature of extreme submillimeter galaxies

Abstract We present the analysis of over 3000 red-Herschel sources ($S_{\mathrm{250\, \mu m}}<S_{\mathrm{350\, \mu m}}<S_{\mathrm{500\, \mu m} }$) using public data from the ALMA archive and the Herschel-ATLAS survey. This represents the largest sample of red-Herschel sources with interferometric follow-up observations to date. The high ALMA angular resolution and sensitivity (θFWHM ∼1 arcsecond; σ1.3 mm ∼ 0.17 mJy beam−1) allow us to classify the sample into individual sources, multiple systems, and potential lenses and/or close mergers. Interestingly, even at this high angular resolution, 73 per cent of our detections are single systems, suggesting that most of these galaxies are isolated and/or post-merger galaxies. For the remaining detections, 20 per cent are classified as multiple systems, 5 per cent as lenses and/or mergers, and 2 per cent as low-z galaxies or Active Galactic Nuclei. Combining the Herschel/SPIRE and ALMA photometry, these galaxies are found to be extreme and massive systems with a median star formation rate of ∼1500 M⊙ yr−1 and molecular gas mass of Mgas ∼ 1011 M⊙. The median redshift of individual sources is z ≈ 2.8, while the likely lensed systems are at z ≈ 3.3, with redshift distributions extending to z ∼ 6. Our results suggest a common star-formation mode for extreme galaxies across cosmic time, likely triggered by close interactions or disk-instabilities, and with short depletion times consistent with the starburst-type population. Moreover, all galaxies with S1.3mm ≥ 13 mJy are gravitationally amplified which, similar to the established $S_{500\mathrm{ \, \mu m}}>100$ mJy threshold, can be used as a simple criterion to identify gravitationally lensed galaxies.

In-situ aberration correction for Laguerre-Gaussian optical tweezers via optimization of orbit shape

We introduce a concept of aberration correction under microscopy that is based on observation of circular Brownian motion of an object driven by orbital angular momentum of a Laguerre-Gaussian (LG) beam. Following the concept, we establish an aberration-correction scheme by using a holographic optical tweezers setup equipped with a spatial light modulator that produces the LG beam as well as corrects the light wavefront. The light wavefront is modified adaptively to improve circular symmetry and uniformity of the orbit of a colloidal dielectric sphere revolving in mid-water under the irradiation of the LG beam. We reveal that the proposed scheme is sensitive to tiny phase difference of less than the accuracy of a highest-grade optical flat, 0.05λ, and is applicable to aberrations of up to the first 21 terms of the Zernike series expansion. The scheme not only improves the quality of optical tweezers but also enables to distinguish individual objective lenses assigned a common product code from difference in aberration-correction patterns. The present contribution therefore provides a useful tool for microscopy and laser fabrication in addition to the immediate application to optical trapping.

The Postmodern Narrative Techniques in Tim O'Brien's "How to Tell a True War Story"

The Vietnam War had an irreversible negative impact on the United States, Vietnam, and the world at large. Its effects extended beyond geopolitics and seeped into the domain of literature, where numerous works have profoundly depicted and contemplated the conflict. Tim O'Brien's "How to Tell a True War Story" stands as a prime example of such literature, set against the backdrop of the Vietnam War. Drawing on Jean-Franois Lyotard's theory of postmodern metanarratives, this paper examines how O'Brien employs postmodern narrative techniques that diverge from traditional grand narratives to articulate the essence of his war fiction. Upon analysis, the paper contends that Tim O'Brien adopts the narrative mode of metafiction, blending narrative and commentary texts alongside real and fictive elements. By doing so, he seeks to alert readers to the constructed nature of both the textual and real worlds, encouraging them to perceive war through the lens of individuals' traumatic war experiences.

Optical degradation correction of manufacturing-perturbed glass-plastic hybrid lens systems via a joint hardware-software optimization framework

Glass-plastic hybrid lens systems are increasingly critical in various optical applications due to their unique advantages and growing demands. Due to limitations in manufacturing processes and costs, the yield rate of glass-plastic hybrid lens systems in mass production struggles to match that of mature all-plastic ones. In this work, we propose a pioneering joint hardware-software optimization framework designed for correcting optical degradation in manufacturing-perturbed glass-plastic hybrid lens systems. Our framework begins with the establishment of a differentiable imaging simulation system that is capable of simulating various manufacturing errors. This system facilitates the preliminary estimation of manufacturing deviations across individual lenses without precise measurements. Subsequently, from the perspective of the hardware assembly process, we integrate active alignment of the glass aspherical lens to mitigate degradation caused by these deviations. Moreover, we introduce a novel and lightweight degradation correction network as post-processing software to address residual optical degradation without fine-tuning for each manufacturing-perturbed lens system, significantly reducing deployment costs for mobile devices. Extensive experiments validate the efficacy of our joint hardware-software optimization framework, showing substantial improvements in imaging quality and enhanced yield rates in mass production. Overall, our framework establishes a new paradigm for optical degradation correction in glass-plastic hybrid lens systems by synergizing the front-end lens assembly process with the back-end degradation correction method. This new paradigm represents an inaugural effort within the optical engineering domain.

Elucidating galaxy population properties using a model-free analysis of quadruply imaged quasar lenses from large surveys

ABSTRACT The population of strong lensing galaxies is a subset of intermediate-redshift massive galaxies, whose population-level properties are not yet well understood. In the near future, thousands of multiply imaged systems are expected to be discovered by wide-field surveys like Rubin Observatory’s Legacy Survey of Space and Time and Euclid. With the soon-to-be robust population of quadruply lensed quasars, or quads, in mind, we introduce a novel technique to elucidate the empirical distribution of the galaxy population properties. Our re-imagining of the prevailing strong lensing analysis does not fit mass models to individual lenses, but instead starts with parametric models of many galaxy populations, which include generally ignored mass distribution complexities and exclude external shear for now. We construct many mock galaxy populations with different properties and obtain populations of quads from each of them. The mock ‘observed’ population of quads is then compared to those from the mocks using a model-free analysis based on a three-dimensional subspace of directly observable quad image properties. The distance between two quad populations in the space of image properties is measured by a metric $\eta$, and the distance between their parent galaxy populations in the space of galaxy properties is measured by $\zeta$. We find a well-defined relation between $\eta$ and $\zeta$. The discovered relation between the space of image properties and the space of galaxy properties allows for the observed galaxy population properties to be estimated from the properties of their quads, which will be conducted in a future paper.

StudyWell: a co-design project for enhancing student mental health and wellbeing through service design and relational welfare

AbstractStudents mental health is declining. StudyWell is a project aiming at positive impact on student mental health in student cities in Norway; by integrating relational welfare with service design, and the study environment as a starting point. We discussfour implementation challenges: First, co-design depends on a shared mindset across disciplinary boundaries. Secondly, balancing the lenses of individuals, community, system and future require facilitation. Thirdly, societal impact requires continuous partner anchoring. Finally, approaches must not further pathologize university student.

Applying individual rigid scleral contact lenses in visual rehabilitation of patients with an irregular corneal surface. Clinical cases

Scleral rigid contact lenses efficiently correct the vision of patients with irregular corneas. Purpose. To study the features of contact correction and visual rehabilitation of patients with irregular corneal surface using individual scleral rigid contact lenses. Results. Three clinical cases of successfully selected rigid individual scleral lenses for patients with an irregular corneal surface that appeared after a penetrating keratoplasty, implantation of intrastromal corneal segments, and eye injury. The expected refractive result was achieved; high tolerance and good adaptation to lenses was revealed. Conclusion. Scleral RCL can be successfully used in patients with irregular cornea to improve visual acuity, reduce the number of aberrations, restore binocular vision and social adaptation.

EnColor: Improving Visual Accessibility with a Deep Encoder-Decoder Image Corrector for Color Vision Deficient Individuals

Individuals with color vision deficiencies (CVDs) often face significant challenges in accessing vital information for decision-making. In response, we introduce EnColor—a deep Encoder-decoder Color corrector for images, enabling individuals with CVDs to perceive the contents in originally intended colorization. Our network architecture is designed to effectively capture essential visual features for reconstructing standard images into color-corrected versions. In particular, our training pipeline is integrated with a CVD simulator so as to ensure the fidelity of output throughout the lens of individuals with impaired color vision. For evaluation, we focus primarily on tomato images, considering the profound impact of color vision deficiencies on practical domains like agri-food systems. Our quantitative results demonstrate that the EnColor model achieves over 16.8% improvement over previously introduced algorithms in terms of color retention, supporting our design choices. Furthermore, a survey with 43 participants provides subjective assessments with the highest scores on our method. Additionally, specific visual examples are presented to highlight accurately restored colors. We also publicly share all our codes of EnColor as well as the baseline methods to ensure reproducibility and facilitate more studies in CVD correction.

Lens injury as acomplication of intravitreal medication injection

Intravitreal medication injections are an efficient and low-risk delivery technique for treating various retinal diseases. Rare serious complications include increased intraocular pressure, vitreous hemorrhage, retinal tears and detachment, intraocular inflammation and endophthalmitis. In the case series presented here, we report iatrogenic lens injuries caused by inadequate performance of intravitreal injections. Amulticenter data collection of patients treated with intravitreal injections with visible iatrogenic lens defects from 2016 to 2023 was retrospectively performed. Lens trauma after intravitreal injections was identified in six cases (69.3±6.5 years). While five cases were observed after anti-VEGF therapy, we identified lens injury after dexamethasone implantation in one patient. Iatrogenic lens injury during intravitreal injection is preventable with the correct injection technique. Knowledge of individual axis length and lens status also helps to avoid this complication.

Comparative analysis of clinical and functional parameters in patients with stable stage II-III keratoconus after implantation of corneal segments and fitting of scleral rigid contact lenses

This study compares the effect of implantation of intrastromal corneal ring segment (ICRS) and fitting of individual scleral rigid contact lenses (RCLs) on visual functions in patients with stage II-III KC after previously performed corneal collagen cross-linking. The Helmholtz National Medical Research Center of Eye Diseases examined and treated 34 patients (69 eyes) aged 18 to 33 years with stage II-III KC. The study included patients who had previously undergone standard corneal collagen cross-linking. Depending on the type of optical correction, the patients were divided into two groups: patients in group 1 underwent ICRS implantation using a femtosecond laser; patients in group 2 were fitted with individual scleral RCLs. Improvement in clinical and functional parameters was observed in both groups. A higher clinical and functional result was achieved in group 2. For patients with stable stage II-III KC, it is advisable to recommend fitting of individual scleral RCLs for visual rehabilitation.

Instrumental study of radiation doses and working conditions for personnel of X-ray surgical teams

The purpose of the study was an experimental assessment of the conditions for the formation and values of equivalent doses of irradiation of the lenses of the eyes, as well as the effective doses of irradiation of personnel in X-ray operating rooms of a cardiological profile. Particular attention to the control of eye lens irradiation is due to the need to harmonize domestic regulatory documents with the new IAEA safety standard GSR Part 3. The study was performed using a complex phantom, including an anthropomorphic phantom of a human head and a water phantom imitating the torso of an X-ray surgical team member. The results of assessments of individual eye lens irradiation doses, obtained both on the basis of integrated measurements by thermoluminescent dosimetry methods, and by calculation based on measurements of the ambient dose equivalent rate at the personnel workplaces, showed that at the maximum operating parameters of the X-ray tube (high voltage and a large number of frames per second), annual doses to the lenses of the eyes, even for assisting personnel, may exceed the new recommended dose limit of 20 mSv. The assessment of the ratio between the doses of irradiation of the whole body (chest), neck and lenses of the eyes showed the possibility of estimating the doses of irradiation of the lenses of the eyes of the assisting personnel of X-ray surgical teams using a thermoluminescent dosimeter placed over a protective apron in the neck area. For the category of personnel under consideration, the priority is to control the irradiation of the lenses of the eyes, and not the whole body.

Thin On-Sensor Nanophotonic Array Cameras

Today's commodity camera systems rely on compound optics to map light originating from the scene to positions on the sensor where it gets recorded as an image. To record images without optical aberrations, i.e., deviations from Gauss' linear model of optics, typical lens systems introduce increasingly complex stacks of optical elements which are responsible for the height of existing commodity cameras. In this work, we investigate flat nanophotonic computational cameras as an alternative that employs an array of skewed lenslets and a learned reconstruction approach. The optical array is embedded on a metasurface that, at 700 nm height, is flat and sits on the sensor cover glass at 2.5 mm focal distance from the sensor. To tackle the highly chromatic response of a metasurface and design the array over the entire sensor, we propose a differentiable optimization method that continuously samples over the visible spectrum and factorizes the optical modulation for different incident fields into individual lenses. We reconstruct a megapixel image from our flat imager with a learned probabilistic reconstruction method that employs a generative diffusion model to sample an implicit prior. To tackle scene-dependent aberrations in broadband , we propose a method for acquiring paired captured training data in varying illumination conditions. We assess the proposed flat camera design in simulation and with an experimental prototype, validating that the method is capable of recovering images from diverse scenes in broadband with a single nanophotonic layer.

Образ Швейцарии М. П. Шишкина через призму концептуальной метафоры

The article studies the role that the conceptual metaphor plays in reconstructing the image of Switzerland. On the material of the literary and historic guidebook The Russian Switzerland by M. P. Shishkin the semantic and stylistic features of metaphors, which are peculiarly encoded definitions of the author’s conceptual meanings, are described. The goal of the paper is to identify the techniques of how the image of Switzerland is conceptualized in its Russian representation. The metaphor’s modeling role is considered on the language and concept levels, a special meta-meaning of the image of Switzerland is registered; it is related to the author’s self-awareness in the space of the foreign culture, to his attempt to comprehend the history of the 20th century through the lens of the conceptual dialogue of cultures. The author’s metaphorical range was analyzed by means of continuous sampling; further, the systemic character in using metaphors in creating the image of Switzerland was revealed. The connection between metaphor and meta-poetic principles of work is noted, the functioning of metaphor in different discourses, related to the history and culture of Russia, is considered. This research is relevant due to the interest of the philological science to the phenomena associated with the thought processes, in particular, on the example of texts that generate artistic and journalistic elements, an interconnection between the author’s thought and the specific nature of the linguistic representation of conceptual meaning of history and culture can be observed. The author’s principle of “coupling” and “combining” is addressed not only in the organization of the textual space (as a genre feature), but in creating a number of conceptual metaphors, which are essential for the thorough understanding of historical reality, its reference points, truth and fallacies through the lens of a certain individual. In the context of M. P. Shishkin’s oeuvre the meta-literary component of the metaphorical models has a special value (space, mirrors/deflection, artefact metaphor).

Problemlösung bei komplizierten kornealen Verhältnissen: Sklerallinsen und deren Anpassung mit neuen modernen Messmethoden

Purpose. The case report describes the follow up fitting with scleral contact lenses for visual rehabilitation in advanced keratoconus and the influence of the scleral fitting characteristics on the daily wearing time as well as the wearing comfort of the contact lenses. Material and Methods. Scleral contact lenses were fitted using Scheimpflug images and analysis of optical coherence tomography cross-sectional images. Based on this data an optimization of the contact lens design could be performed. Results. In the present case, a significant improvement in visual acuity, daily wearing time and wearing comfort was achieved due to scleral lens re-fitting with individual scleral lens sagittal height calculation and custom fitting according to corneo-scleral profile measurement data. Conclusion. Scleral lenses can be a good alternative to other contact lens treatments to achieve visual rehabilitation in complex corneal situations. Analysis of the corneo-scleral profile by Scheimpflug technique and accurate evaluation of the sagittal height are of great benefit, in addition to the assessment of the fitting and landing zone of scleral lenses by anterior segment OCT. This results in significant time savings for the fitting and leads to a more physiologically compatible contact lens treatment result. Keywords keratoconus, scleral lenses, optical coherence tomography (OCT), corneo-scleral profile (CSP)

Study of silicone hydrogel contact lenses’ surface reflection characteristics using confocal microscopy

The physical and chemical properties of contact lenses (CLs) differ significantly from one another. This is already covered by the FDA classification, which divides soft lenses into groups and subgroups for additional characteristics. The differences relate to both the interior and surface of the lens. Several differences in the surface characteristics of individual contact lenses have been studied and demonstrated to date. However, one of their fundamental physical properties, that is light reflection or, quantitatively, reflectance has not been compared. This paper describes the surface differences of a range of silicone-hydrogel (SiHy) lenses using reflectance confocal microscopy. It shows the relationship between the amount of light reflected from the lens surface and the material parameters. Common SiHy lens materials were used in the study, including two lenses with surface modifications. Light incident at the interface between two media (phosphate-buffered saline and lens) with different refractive indices is partially reflected. The normalized results show significant differences between the reflection signals (1 vs 0.07), and that they are not correlated with the refractive index (R2 = 0.5536). For the water content (%H2O), a general trend was observed that the higher the %H2O, the lower the reflection signal is (R2 = 0.8105). The reflection signal and surface modulus show the best correlation. (R2 = 0.9883). The proposed CLs analysis method, using reflectance confocal microscopy, provides data to differentiate between lenses with and without surface modifications.

The Use of Fresnel Lenses in LED Sources of Local Illumination to Оptimize the Distribution of Illumination of the Working Plane

For widely used LED sources there is a sharp decrease in the illumination of the working plane from the center to the edge. The purpose of this study was to analyze the effectiveness of Fresnel lenses usage as a fairly simple and technological element to increase the uniformity of illumination created by LED lamps of local lighting.A method has been developed for calculating of the distribution of illumination created by the combination of “LED matrix – Fresnel lens” when the distance between the lens and the matrix is less than the focal length of the lens. Comparison of the calculation results and experiments for the case when the lens is located at a distance of 50 cm from the working plane indicates the correctness of the developed calculation method. This made it possible to use this technique to solve the problem of improved uniformity of illumination distribution in the working plane of local lighting LED sources.It was found that the change in the distance between the matrix and the lens in the range of 0.5–1.5 cm affects the maximum illumination and its uniformity to a lesser extent than the change in focal lengths in the range of 10–100 cm. Analytical dependences of the uniformity of the working surface illumination as a function of the Fresnel lens focal length and its distance to the LED matrix were obtained for three cases. In the first case one lens is used for the entire matrix while the axes of symmetry of the light intensity curves of LEDs are parallel to the axis of the lens. In the second case one lens is also used for the entire matrix, but the continuations of the axes of symmetry of the light intensity curves pass through the front focus of the lens. In the third one an individual Fresnel lens is used for each LED. It is established that for all three cases dependencies have almost the same character. Therefore, the choice of using one of these three options may be due to manufacturability, cost-effectiveness, thermal stability, and other considerations.Calculations using the above-mentioned analytical dependences made it possible to determine values of the parameters of the “LED matrix – Fresnel lens” system at which the indicators of illumination and uniformity meet the standards’ requirements.

Unpacking the Complexities of Emotional Responses to External Feedback, Internal Feedback Orientation and Emotion Regulation in Higher Education: A Qualitative Exploration

Research suggests that unpleasant emotions induced by feedback may reduce its efficiency in enhancing students’ performance, which is a crucial issue to address in education. In the context of Chinese language instruction in higher education, this study sought to investigate how students regulate their emotions as a result of feedback through the lens of individuals’ feedback orientation. In light of the feedback orientation lens and its conceptual framework, we applied in-depth qualitative interviews to explore how students experienced feedback, the negative emotions they experienced, and the emotion regulation strategies they used. Eleven undergraduates across years one to five joined our in-depth interviews. Students reported negative emotions when they received feedback that did not live up to their expectations or was unrealistic for them to accept. However, students’ feedback orientation supported their emotion regulation techniques, which in turn supported students’ adaptive feedback processing to interpret and take action to use feedback for academic performance improvement. Students also actively sought further teacher feedback or peer support to deal with a wide range of negative emotions. These findings imply the significance of fostering in students a high level of feedback orientation and the necessity of additional empirical investigation into the relationships between feedback orientation and emotional well-being in higher education. By shedding light on how students regulate the emotions that external feedback causes in them, the study adds valuable qualitative findings to the existing literature on positive psychology research in terms of emotions and emotion regulation. It also emphasizes how crucial students’ personal feedback orientation is for improving emotional well-being in the context of feedback.

Geochemical and remote sensing integrated with satellite gravity data of Darhib and Atshan talc deposits, South Eastern Desert, Egypt

The current contribution conducted new geochemical, remote sensing integrated with gravity detailed studies of talc deposits to identify the talc protolith as well as its extension, depth, and structures. There are two examined areas, distributed from north to south, Atshan and Darhib and both belong to the southern sector of the Egyptian Eastern Desert. They occur as individual lenses or pocket bodies in ultramafic-metavolcanics following NNW-SSE and E-W shear zones. Geochemically, among the investigated talc, Atshan samples have high contents of SiO2 (av. 60.73 wt.%), and higher concentrations of transition elements such as Co (av. 53.92 ppm), Cr (781 ppm), Ni (av. 1303.6 ppm), V (av. 16.67 ppm), and Zn (av. 55.7 ppm). Notably, the examined talc deposits contain low contents of CaO (av. 0.32 wt.%), TiO2 (av. 0.04 wt.%), SiO2/MgO (av. 2.15), and Al2O3 (av. 0.72 wt.%), which is comparable with ophiolitic peridotite and forearc setting. False color composite (FCC), principal component analysis (PCA), minimum noise fraction (MNF), and band ratio (BR) have been used to distinguish talc deposits in the investigated areas. Two new proposed band ratios were created to separate talc deposits. FCC band ratios (2/4, 4/7, 6/5) and (4 + 3/5, 5/7, 2 + 1/3) have been derived to focus on talc deposits in two case studies, Atshan and Darhib areas. The application of regional, residual, horizontal gradient (HG), and analytical signal (AS) techniques to gravity data are used in interpreting the structural directions of the study area. The analysis of this technique displays several notable faults trending in NW–SE, NE–SW, NNW–SSE, and E–W directions. Two techniques of gravity depth calculation were applied in the study areas, namely source parameter image (SPI), and Euler deconvolution (EU). The analysis of these techniques reflects that the depth of subsurface sources ranges between 383 and 3560 m. Talc deposits may be attributed to greenschist facies metamorphism or to a magmatic solution that is (associated with granitic intrusions) interacted with the surrounding volcanic rocks forming metasomatic minerals.