Variation Of Angle Research Articles

Magnetic field density concentrated permanent magnet structure for electromagnetic MEMS scanning mirror

The study investigates the inadequacy of driving torque in large-diameter Micro-electro Mechanical Systems Electromagnetic Scanning Mirrors (MEMS-ESM) and introduces fresh insights into the power efficiency of traditional MEMS-ESM devices. A novel permanent magnet structure (PMS) and driving principle are devised, drawing upon the phenomenon of concentrated magnetic field density and a custom-designed PMS inner profile. In comparison to L-shaped and I-shaped PMSs, the proposed PMS delivers up to 3.48 times and 3.76 times greater driving torque within the same form factor. Moreover, the optimized proposed PMS has been experimentally proven to reduce power consumption by 53.3% and 81.4% and reduce total driving current by 31.3% and 55.0%, making it the sole solution that conforms to the safe current range. Additionally, the research analyzes the impact of variations in the optical scanning angle on the optimal PMS design. It is noteworthy that the proposed PMS enables the substitution of L-type and I-type PMSs with smaller package sizes, all while preserving torque, thus promoting the miniaturization of MEMS-SM.

Integrating Pix2Pix and computational fluid dynamics for enhanced indoor airflow prediction: A case study with wing-walls

Computational Fluid Dynamics (CFD) is often used for analyzing natural ventilation but is limited in early design stages due to its high computational demands and the need for detailed inputs. To overcome such limitations of CFD simulation, this paper proposes a method using a conditional Generative Adversarial Network (cGAN) based image-to-image translation (Pix2Pix) to predict the indoor airflow condition. Compared to other traditional machine learning models that predict averaged values like indoor air velocity, Pix2Pix can predict contour plot of indoor airflow for the given building floor plan image, which provides more intuitive feedback to designers. The proposed method was tested to understand indoor air movement caused by wing-walls attached to the windows. The model was trained using 1153 pairs of floor plan images, incorporating variations in window widths, wing-wall depth, wing-wall angle, wind speed, and wind direction. It achieved a prediction accuracy of 94 % and produced results in less than a second. Moreover, the model showed relatively better performance with the changes in windows and wing-walls properties rather than wind properties. This high performance indicates that Pix2Pix can serve as an efficient proxy model of conventional CFD simulations, helping designers optimize ventilation in building designs at an early stage without the need for complex inputs.

Multicolour photometry of LEO mega-constellations Starlink and OneWeb

ABSTRACT The development of low earth orbit (LEO) mega-constellation fundamentally threatens ground-based optical astronomical observations. To study the photometric properties of the LEO mega-constellations, we used the Xinglong 50 cm telescope to conduct a large-sample, high-precision, and multicolour target-tracking photometry of two typical LEO mega-constellations: Starlink and OneWeb. Over a three-month observation period starting on 2022 January 1, we collected 1447 light curves of 404 satellites in four typical versions: Starlink v1.0, DarkSat, VisorSat, Starlink v1.5, and OneWeb. According to data statistics, Starlink v1.0 has the smallest median magnitude at clear and Sloan Digital Sky Survey gri band, and OneWeb is the dimmest bus. The brightness of Starlink v1.5 is slightly brighter than VisorSat. We construct a detailed photometric model with solar phase angle variations by calculating the illumination-visibility geometry based on the orbital parameters. Our data analysis shows that the solar phase angle is the significant characteristic which influencing Starlink satellites’ brightness, but it is not sensitive to OneWeb satellites. VisorSat and Starlink v1.5 versions, which are equipped with deployable visors, have significantly reduced scattered light compared to the previous Starlink v1.0 version. The multiband LOWESS and colour index are analysed in characterizing the energy and colour features of LEO mega-constellation satellites. This work found that the proportion of scattered sunlight mitigation achieved with VisorSat and Starlink v1.5 was 55.1 and 40.4 per cent, respectively. The colour index of different buses shows an evident clustering feature. Our observation and analysis could provide valuable quantitative data and photometric models, which can contribute to assessing the impact of LEO mega-constellations on astronomical observations.

Numerical Simulation on the Spray Angle of the Dual-layer Hole Nozzle in a Partition Combustion System of the Diesel Engine

To study the effect of the spray angles of the dual-layer hole nozzle on the combustion and emissions performance in the partition combustion system, the in-cylinder spray, mixture formation and combustion processes of the new combustion system were simulated and investigated using AVL FIRE software. The results show that, compared with the variation of the lower-layer spray angles, the change of the upper-layer spray angles has a great influence on the instantaneous heat release rate. The increasing spray angles of the lower-layer holes lead to reduced peak values of the heat release rate in the cylinder. In all the spray angle cases, the first fire area of the cylinder is in the B zone of the combustion chamber. Compared with lower-layer spray angle, the upper-layer spray angle has a greater impact on the airflow disturbance in the combustion chamber. Appropriately increasing the upper-layer spray angle facilitates the mixing of fuel and air in the combustion chamber and reduces the unburnt fuel equivalence ratio. When the spray angles of the upper- and lower-layer holes are 157° and 112°, respectively, the combustion indicates power has the largest value of 12.18 kW. At the same time, the Soot emission is also the smallest, with a value of 0.52 g/kW·h.

Research on High-Stability Composite Control Methods for Telescope Pointing Systems under Multiple Disturbances.

During the operation of space gravitational wave detectors, the constellation configuration formed by three satellites gradually deviates from the ideal 60° angle due to the periodic variations in orbits. To ensure the stability of inter-satellite laser links, active compensation of the breathing angle variation within the constellation plane is achieved by rotating the optical subassembly through the telescope pointing mechanism. This paper proposes a high-performance robust composite control method designed to enhance the robust stability, disturbance rejection, and tracking performance of the telescope pointing system. Specifically, based on the dynamic model of the telescope pointing mechanism and the disturbance noise model, an H∞ controller has been designed to ensure system stability and disturbance rejection capabilities. Meanwhile, employing the method of an H∞ norm optimized disturbance observer (HODOB) enhances the nonlinear friction rejection ability of the telescope pointing system. The simulation results indicate that, compared to the traditional disturbance observer (DOB) design, utilizing the HODOB method can enhance the tracking accuracy and pointing stability of the telescope pointing system by an order of magnitude. Furthermore, the proposed composite control method improves the overall system performance, ensuring that the stability of the telescope pointing system meets the 10 nrad/Hz1/2 @0.1 mHz~1 Hz requirement specified for the TianQin mission.

A Solvent-Templated Porous Liquid Crystal Elastomer with Tactile Sensation beyond Reversible Actuation toward Versatile Artificial Muscles.

Liquid crystal elastomers (LCEs), as a classical two-way shape-memory material, are good candidates for developing artificial muscles that mimic the contraction, expansion, or rotational behavior of natural muscles. However, biomimicry is currently focused more on the actuation functions of natural muscles dominated by muscle fibers, whereas the tactile sensing functions that are dominated by neuronal receptors and synapses have not been well captured. Very few studies have reported the sensing concept for LCEs, but the signals were still donated by macroscopic actuation, that is, variations in angle or length. Herein, we develop a conductive porous LCE (CPLCE) using a solvent (dimethyl sulfoxide (DMSO))-templated photo-cross-linking strategy, followed by carbon nanotube (CNT) incorporation. The CPLCE has excellent reversible contraction/elongation behavior in a manner similar to the actuation functions of skeletal muscles. Moreover, the CPLCE shows excellent pressure-sensing performance by providing real-time electrical signals and is capable of microtouch sensing, which is very similar to natural tactile sensing. Furthermore, macroscopic actuation and tactile sensation can be integrated into a single system. Proof-of-concept studies reveal that the CPLCE-based artificial muscle is sensitive to external touch while maintaining its excellent actuation performance. The CPLCE with tactile sensation beyond reversible actuation is expected to benefit the development of versatile artificial muscles and intelligent robots.

THE INFLUENCE OF TILT ANGLE ON THE DAILY PROFILE TOTAL ENERGY OF PHOTOVOLTAIC POLYCRYSTAL

This preliminary study aims to determine the daily profile of the power output generated from solar panels, with variations in the house’s roof angles of 15º, 0º, 15º. Tilt angle investigation expects to discover the impact of placing solar panels on the slope of the tile used on the house’s roof. The collecting data of this study was investigated the data of current and voltage every hour that produced by solar panel. Besides, this study also comparing the result of total energy output value for daily profile of solar panel during ten hour per day (start from 7 am to 5 pm). The results show that solar panels with an angle of -15º at 07:00 – 10:00 WIB have higher output voltage and current than other angle variations. At a tilt angle of 0º, the output voltage and current of the solar panel are higher at 11:00-14:00 WIB, while at a tilt angle of 15º in the afternoon. Based on observations, each solar panel with exposure for 10 hours obtained the total energy value for polycrystalline solar panels with a tilt angle of -15º of 258.44 Wh, solar panels with an angle of 0º obtained an energy value of 263.64 Wh, and a tilt angle of 15º obtained energy values 260.69 Wh. The photonic energy emitted for 10 hours is 2097.47 Wh. The energy efficiency value for each polycrystalline solar panel is 12.32% for the angle of -15º, the angle of 0º is 12.57%, and 12.43% for the angle of 15º. In conclusion, variations in the angle of the solar panels have significant effect on the voltage, current, and energy generated from polycrystalline solar panels in every hour. However, based on the data result the total energy exposure and the efficiency value for each variation angle has no significant different. Pyramid-shaped house roof construction has the advantage of increasing the value of the cross-sectional area of the tile, which has the opportunity to install wider-sized solar panels so that a greater value of electrical energy is obtained.

Theoretical triple differential cross sections for ionization of N 2 and CH 4 molecules by electron impact

We present the angular distribution of electron emission by calculating the triple differential cross sections for (e, 2e) process on N 2 and CH 4 by using the three-body formalism of molecular first Born approximation (MFBA), two-Coulomb wave (M2CW), and three-Coulomb wave (M3CW) models, respectively. In these models, a Coulomb distorted wave is considered for the motion of the incident electron. We have considered the continuum-continuum correlation effect by choosing the final state as the three-Coulomb and two-Coulomb wave functions in M3CW and M2CW models, whereas the ejected electron is affected by a single centre field of the target in the MFBA model. In the M2CW model, the interaction between scattered electron-residual target ion has been described as a plane wave. The distinguishing feature among the three models has been noted in the TDCS as a strong binary peak with and without a recoil peak for several electron emission energies at fixed scattering angle. In the case of N 2 molecule, the TDCS shows oscillatory behaviour with the variation of the electron emission angle. The positions of the binary peak obtained by our theoretical models are well established by the experimental findings, but a large deviation is found in the region of the recoil peak. The contributions of TDCS for different molecular orbitals of the molecules to the spectrum of angular distributions at different electron emission energies have also been analyzed. Finally, a comparison is made with the measurement in coplanar asymmetry geometry. Overall, good agreement was found between experiments and M3CW theory.

ESTABLISHING THE TYPE OF TEXTURE FORMING PARTICLES ON HYDROPHOBIC PROPERTIES OF COATINGS

In this study, the primary objective is to investigate the impact of various particles on the hydrophobic characteristics of a coating. The experimental approach involves employing a conventional chemical precipitation method to fabricate ZnO particles. Subsequently, composite materials of SiO2-ZnO are synthesized based on these ZnO particles. The coating is formulated using styrene-butyl methacrylate as the principal raw material. Different particles, namely TiO2, SiO2, ZnO, and ZnO-SiO2, are individually added to the coating, allowing for the exploration of the influence of distinct mass ratios on the resulting hydrophobic angle. The findings of this investigation reveal a notable trend in the contact angles of the four materials as the mass ratio varies. Initially, the contact angles experience an increase, followed by a subsequent decrease. Remarkably, when the mass ratio of ZnO-SiO2 is set at 60%, the contact angle achieves an impressive 152.5°, meeting the criteria for superhydrophobicity. In comparison to a pure acrylate polymer coating, the incorporation of particles induces agglomeration on the coating's surface. This agglomeration can be conceptualized as clustered particles, contributing to heightened surface roughness in the coating and consequently enhancing its hydrophobic properties. The observed variations in contact angles underscore the nuanced interplay between mass ratios and hydrophobicity, shedding light on the optimization possibilities for achieving superhydrophobic coatings. The study suggests that manipulating the composition of particles within the coating formulation can be a viable strategy for tailoring hydrophobic properties. Furthermore, the surface modifications induced by particle incorporation provide valuable insights into the underlying mechanisms governing the hydrophobic behavior. This research contributes to the broader understanding of materials science and surface engineering, offering potential applications in areas where superhydrophobic coatings are desirable, such as anti-fouling surfaces, self-cleaning materials, and advanced protective coatings. The exploration of such multifaceted relationships between particle composition and hydrophobicity holds promise for the development of innovative materials with tailored surface properties.

Numerical studies on shock wave and boundary layer interaction in the high-load turbine rotor cascades

Design of transonic high-load turbine is the essential approach to improve thrust-to-weight ratio of gas turbine engines. The shock wave and boundary layer interaction (SWBLI) in high-load turbine is one of the important unsteady sources and the main source of loss in turbine stages. In order to study mechanism of SWBLI in high-load turbine, rotor blades with loading coefficients range from 1.6 to 2 were designed and Delayed Detached Eddy Simulations (DDES) were carried out. The influences of loading coefficient, exit isentropic Mach number and incidence angle on characteristics of shock wave, SWBLI as well as flow details in the blade passages were compared. Results indicated the shock wave was generated and enhanced as exit isentropic Mach numbers increased leading to the increase of 2.8% in the total pressure loss coefficient. There was not significant difference in the total pressure loss coefficient as loading coefficient increased, however the shock wave was stronger and the separation bubble was longer at the loading coefficient of 1.6. Meanwhile, the influence of strong separation near the leading edge of suction surface induced by variation of incidence angles on the characteristics of the shock wave and the loss was also obvious.

Effects of non-uniform wavy ribs on flow and heat transfer characteristics of turbine blade cooling channel

Aiming at the problem of reduced heat transfer performance and uneven distribution along the ribbed channel in aero-engine turbine blades, the influence mechanism of rib height, rib angle and fillet radius on the flow and heat transfer characteristics of wavy rib cooling channel under different inlet Reynolds numbers is analyzed by experimental and numerical methods. The research illustrates that the non-uniform change of the rib height has the most profound influence on the heat transfer performance of the ribbed channel. Schemes featuring larger initial and final rib heights demonstrate superior heat transfer performance and uniformity, with the friction factor primarily determined by the maximum rib height. The optimal rib height variation scheme shows a 22.6 % increase in overall Nu/Nu0, with only a 6 % reduction in heat transfer evenness. The non-uniform variation of rib angle and fillet radius mainly affects the local heat transfer and friction factor. Increasing Reynolds number, the distribution of friction factor of the large rib height scheme changes more drastically. At a large Reynolds number (Re = 40000), the enhanced heat transfer in the middle and rear sections of the channel due to the larger rib angle and fillet radius comes at the cost of increased pressure loss.

Experimental Study of Direct Shear Properties of Anisotropic Reservoir Shale

Understanding the shear mechanical properties of shale reservoirs is of great significance in the study of the formation stability around horizontal shale wells and the propagation and evolution of fractures for shale fracturing. However, the existing direct shear test results are limited due to small sample sizes and low shear rates. Based on previous experimental research results, the mechanical properties of anisotropic reservoir shale in direct shear tests with different experimental conditions were explored in this study. It was found that the shear mode, shear strain rate, and normal stress have a significant impact on the deformation and failure characteristics of shale. The peak shear displacement, peak shear strength, and shear stiffness of shale present an increasing trend of fluctuation, with an increase in the bedding angle. The peak shear strength of shale decreases with an increase in the shear strain rate, and this decrease trend descends with an increase in the shear strain rate. The shape of the shear fracture zone and the shear fracture mode of shale exhibit bedding effect characteristics. The fractal dimension of the shale shear fracture surface morphology shows a trend of fluctuation with the variation in the bedding angle. Further, the shear strain rate was found to play a dominant role in the fractal dimension of the shear fracture surface. The larger shear strain rate strengthens the bedding effect of the roughness for the shear fracture surface morphology. The results of this study provide a theoretical reference for determining the engineering geomechanics characteristics of shale reservoirs.

The Efficacy of Anterior Cruciate Ligament Reconstruction with Peroneus Longus Tendon and its Impact on Ankle Joint Function.

Peroneus Longus Tendon (PLT), a viable anterior cruciate ligament (ACL) graft, shares similar biomechanics, making it suitable for reconstruction. Controversy exists over whether PLT transplants affects the donor ankle joint. The purpose of this study was to examine the recovery of knee joint function following arthroscopic ACL restoration using autologous PLT and its influence on the donor ankle joint. A retrospective analysis was conducted on 65 patients with ACL rupture who underwent PLT graft reconstruction in our hospital from January 2016 to December 2021. A three-dimensional gait analysis of the bilateral knee and ankle joints was performed postoperatively using an Opti_Knee three-dimensional motion measurement and analysis system-Yidong Medical Infrared Motion Gait Analyzer. Knee function scores and changes in the range of motion of the bilateral knee and ankle joints were collected. The analysis of preoperative and postoperative joint function scores, bilateral knee and ankle mobility was performed by t-tests. One year after surgery, the patients' International Knee Documentation Committee (IKDC) scores, Knee Injury and Osteoarthritis Outcome Scores (KOOSs), and Lysholm scores were significantly improved compared to preoperative scores, with statistically significant differences (p < 0.05). There was no statistical difference in the American Orthopedic Foot and Ankle Society (AOFAS) score of the donor ankle joint before and after surgery (p > 0.05). During different gait cycles, there was no statistical difference in knee joint mobility between the affected and healthy sides (p > 0.05), but there was a statistical difference in the inversion and eversion angle of the donor ankle joint during the support phase (p < 0.05). ACL reconstruction using the PLT can yield satisfactory knee joint function. However, it does affect inversion and eversion in the donor ankle joint, necessitating postoperative exercises. Similar subjective function ratings for both operated and non-operated feet, despite increased inversion-eversion motion in the operated foot, may be influenced by the subjective nature and margin of error in the AOFAS Ankle-hindfoot score, along with the relatively small variation in ankle inversion-eversion angles.

Communication—Oscillating Oxygen Concentration Transport through PEM Fuel Cell Gas Diffusion Layer: Variation of the Phase Angle

Recently, it was shown that performance of the cathode catalyst layer in PEM fuel cell dramatically improves if the oxygen concentration (OC) at the catalyst/ gas diffusion layer (GDL) interface oscillates in–phase with the overpotential. However, OC oscillations could only be organized in the cathode channel. Does transport through the GDL affect the phase angle of OC oscillations? Below, it is shown that at low frequencies below 1 Hz, the GDL does not change this phase angle. At high frequencies, the phase angle after transport through the GDL is −3π/4 regardless of the GDL parameters.

Adiabat-to-Diabat Angle in Seam Space: Renner-Teller-Type and Pseudo-Jahn-Teller-Type Problems.

In this study, we examine the adiabat-to-diabat (ATD) angles for trajectories in 2-dimensional vibrational subspace of the seam space of two degenerate states. In circulating around the tangential touching degeneracy center, the ATD angle is changed by or 0, similar to the Renner-Teller problem and the pseudo-Jahn-Teller problem, respectively. These ATD angle profiles may be indistinguishable from those of circulating multiple conical intersections or a pseudo-Jahn-Teller center. Methods to discern those seemingly indistinguishable cases are proposed. A sharp zigzag variation of the ATD angle is seen as a feature for trajectories that graze a pseudo-Jahn-Teller-type tangential touching center, in contrast to the monotonic steep variation for grazing a conical intersection or a Renner-Teller-type tangential touching center.

Tunable quantized spin Hall effect of light in graphene

The spin Hall effect of light is an appealing toolset for metrology that holds incredible potential for precision measurements due to its high sensitivity to the refractive index and nanostructure physical parameters. Here, we theoretically examine the quantized spin Hall effect of light on the surface of a monolayer graphene–substrate system subjected to an external perpendicular magnetic field. We discuss the impact of Landau levels induced by the external magnetic field B and the photon energy on magneto-optical conductivities and Fresnel reflection coefficients. We find that the spin-dependent splittings in graphene exhibit quantized characteristics due to the Landau levels quantization of the magneto-optical conductivities and Fresnel’s reflection coefficients near the Brewster angle. Moreover, the spin-dependent shifts are quantized and show oscillatory behavior with changes in the magnetic field and the photon energy. Our results manifest that the quantized photonic spin-dependent separations are sensitive to variations in the incidence angle, magnetic field, and incident photonic energies. The quantized spin-dependent splitting opens a promising route to find the quantized Hall conductivity and discrete Landau levels in the monolayer graphene by a direct optical weak measurement.

Through-Drop Imaging of Liquid-Solid Interfaces: From Contact Angle Variations Along the Droplet Perimeter to Mapping of Contact Angles Across a Surface.

When a droplet interacts with a water-repellent surface, its triple-phase contact line typically exhibits varying contact angles, which can vary from point-to-point across the surface. Consequently, measuring the contact angles along the contact line would provide a better representation of the wetting properties of the surface than a single average contact angle. However, an effective method for estimating the local contact angle along the contact line on opaque hydrophobic surfaces is currently lacking. Here we present a method that combines through-drop imaging of the wetting interface during a sliding experiment with Finite Element Modeling of the droplet to estimate contact angle values along the contact line. Using this method, the mean advancing and receding contact angles were measured on four types of hydrophobic samples with contact angles between 99 and 178.9°. The method was further used to produce detailed advancing and receding contact angle maps of surfaces with wetting patterns with an unprecedented resolution of 3 μm.

Transient Phenomena of Dynamic Contact Angle in Micro Capillary Flows

This study is devoted to investigating the dynamics of liquid driven by capillary force in a circular tube. A microscope was used to visualize the meniscus movement and the contact angle. The experiments were carried out with glycerin–water mixtures with viscosity ranging from 0.21 to 1.36 Pa∙s by filling the test liquid in a borosilicate glass tube with an inner diameter of 200 μm. The wetting distances of the meniscus with time were compared with the theoretical solution by considering the dynamic variation of contact angle. The results show that the theoretical solution agrees well with experimental data due to the reflection of the actual dynamic contact angle for the transient motions in the developing entrance region. In view of momentum balance, variations of dominant force according to the time were determined by separated inertial periods, such as inertial, inertial-viscous, and viscous time stages.

Optical Analysis Method for Turbid Media Based on Wedge-Shaped Cells at Different Angles.

The wedge-shaped sample cell, by offering a comprehensive representation of scattering information in turbid media, significantly enhances the informational content conveyed by spectral images compared to flat sample cells. To further refine the accuracy of turbid medium component detection utilizing wedge-shaped sample cells, this work undertakes modeling and analysis of the influence of different wedge angles on detection precision. In this study, employing a 5° gradient in the incident angle of light, we investigate the impact of incident angles ranging from 10 to 45° on the turbid medium component analysis. Validation experiments are performed by utilizing solutions of Indian ink and fat emulsion at varying ratios. Experimental findings demonstrate that under identical experimental conditions, the wedge-shaped sample cell model at an incident angle of 35° yields optimal analysis results. Utilizing partial least-squares regression (PLSR) for the corresponding optical parameters, the highest value of Rp reached 0.980, with an RMSEP of 0.002. When compared to the model with a 30° incident angle, Rp increased by 0.033, and RMSEP decreased by 0.008. In comparison to the flat sample cell model, Rp increased by 0.041, and RMSEP decreased by 0.004. This study, through continuous variation of wedge angles and PLSR modeling and prediction, further enhances the accuracy of turbid medium component detection, laying an experimental foundation for subsequent analysis of turbid medium components based on wedge-shaped sample cells.

Technical note: Visual, rapid, scintillation point dosimetry for in vivo MV photon beam radiotherapy treatments.

While careful planning and pre-treatment checks are performed to ensure patient safety during external beam radiation therapy (EBRT), inevitable daily variations mean that in vivo dosimetry (IVD) is the only way to attain the true delivered dose. Several countries outside the US require daily IVD for quality assurance. However, elsewhere, the manual labor and time considerations of traditional in vivo dosimeters may be preventing frequent use of IVD in the clinic. This study expands upon previous research using plastic scintillator discs for optical dosimetry for electron therapy treatments. We present the characterization of scintillator discs for in vivo x-ray dosimetry and describe additional considerations due to geometric complexities. Plastic scintillator discs were coated with reflective white paint on all sides but the front surface. An anti-reflective, matte coating was applied to the transparent face to minimize specular reflection. A time-gated iCMOS camera imaged the discs under various irradiation conditions. In post-processing, background-subtracted images of the scintillators were fit with Gaussian-convolved ellipses to extract several parameters, including integral output, and observation angle. Dose linearity and x-ray energy independence were observed, consistent with ideal characteristics for a dosimeter. Dose measurements exhibited less than 5% variation for incident beam angles between 0° and 75° at the anterior surface and 0-60 at the posterior surface for exit beam dosimetry. Varying the angle between the disc surface and the camera lens did not impact the integral output for the same dose up to 55°. Past this point, up to 75°, there is a sharp falloff in response; however, a correction can be used based on the detected width of the disc. The reproducibility of the integral output for a single disc is 2%, and combined with variations from the gantry angle, we report the accuracy of the proposed scintillator disc dosimeters as ±5.4%. Plastic scintillator discs have characteristics that are well-suited for in vivo optical dosimetry for x-ray radiotherapy treatments. Unlike typical point dosimeters, there is no inherent readout time delay, and an optical recording of the measurement is saved after treatment for future reference. While several factors influence the integral output for the same dose, they have been quantified here and may be corrected in post-processing.