A calibration method for a line-structured optical system, employing a hinge-connected double-checkerboard stereo target, is presented in this paper. Randomly, the target shifts to multiple positions and orientations throughout the area of the camera's spatial measurements. Through the acquisition of a single target image under line-structured light conditions, the 3D coordinates of the features on the light stripes are calculated using the target plane's external parameter matrix, relative to the camera's coordinate system. Following denoising, the coordinate point cloud is utilized to generate a quadratic fit of the light plane. In comparison to the standard line-structured measurement system, the proposed method facilitates the concurrent acquisition of two calibration images, therefore rendering a single line-structured light image sufficient for the calibration of the light plane. System calibration efficiency, characterized by high accuracy, is not limited by the lack of strict rules for the target pinch angle and placement. This method's experimental results indicate a peak RMS error of 0.075mm, offering a more streamlined and effective process to meet the technical demands of industrial 3D measurement applications.

A four-channel, all-optical wavelength conversion system, highly efficient and based on four-wave mixing, is proposed and experimentally verified using a directly modulated, three-section, monolithically integrated semiconductor laser. This wavelength conversion unit allows for adjustable wavelength spacing, achieved by tuning the laser bias current. A demonstration in this work utilizes a 0.4 nm (50 GHz) setting. An experimental trial involved switching a 50 Mbps 16-QAM signal, centered in the 4-8 GHz band, to a selected path. A wavelength-selective switch determines whether up- or downconversion is performed, leading to a potential conversion efficiency of -2 to 0 dB. This work's innovative photonic radio-frequency switching matrix technology directly contributes to the integration of satellite transponder systems.

Relative measurements form the basis for a new alignment method, which employs an on-axis test setup built around a pixelated camera and a monitor. By seamlessly integrating deflectometry and the sine condition test, this new method avoids the tedious task of physically shifting the testing device between diverse field points, enabling accurate assessment of the system's alignment by evaluating both its off-axis and on-axis performance. Moreover, this approach can prove to be a highly economical choice for specific projects, acting as a monitor. A camera can potentially replace the return optic and interferometer, components typically needed in conventional interferometric methods. A meter-class Ritchey-Chretien telescope serves as our illustrative tool for explaining the new alignment technique. Along with our findings, we introduce a new metric, the Misalignment Indicator Metric (MMI), that quantifies the wavefront error transmitted due to system misalignment. We employ simulations, beginning with a telescope experiencing misalignment, to demonstrate the concept's validity and prove its superior dynamic range compared to the interferometric method. In spite of the presence of realistic noise levels, the novel alignment method achieves a significant two-order-of-magnitude improvement in the final MMI score after three rounds of alignment. Perturbed telescope models initially exhibited a measurement of approximately 10 meters, but alignment procedures considerably refine the measurement to a pinpoint accuracy of one-tenth of a micrometer.

The fifteenth topical meeting on Optical Interference Coatings (OIC) in Whistler, British Columbia, Canada, ran for six days, from June 19th to 24th, 2022. This Applied Optics issue features selected presentations from the conference. The OIC topical meeting, a crucial juncture for the international community in optical interference coatings, takes place precisely every three years. This conference offers attendees unparalleled opportunities to share knowledge of their research and development innovations and build alliances for future collaborative projects. The subjects discussed at the meeting encompass a broad spectrum, starting with fundamental research in coating design and material science, moving to advanced deposition and characterization methods, and eventually progressing to a wide range of applications, such as green technologies, aerospace, gravitational wave detection, telecommunications, optical instruments, consumer electronics, high-power and ultrafast lasers, and other disciplines.

This paper examines the method of increasing the output pulse energy of an all-polarization-maintaining 173 MHz Yb-doped fiber oscillator using a 25 m core-diameter large-mode-area fiber. Employing a Kerr-type linear self-stabilized fiber interferometer, the artificial saturable absorber effects non-linear polarization rotation within polarization-maintaining fibers. A highly stable mode-locked steady state, achieved within a soliton-like operational regime, is showcased, generating an average output power of 170 milliwatts and a total pulse energy of 10 nanojoules, partitioned between two output ports. Through experimental parameter comparison with a reference oscillator fabricated using 55 meters of standard fiber components, each of a consistent core size, a 36-fold increase in pulse energy was observed alongside a decrease in intensity noise within the high-frequency range exceeding 100kHz.

A microwave photonic filter, termed a cascaded microwave photonic filter, exhibits superior performance by combining a microwave photonic filter (MPF) with two distinct filter architectures. An experimentally validated high-Q cascaded single-passband MPF is introduced, employing stimulated Brillouin scattering (SBS) and an optical-electrical feedback loop (OEFL). The pump light used in the SBS experiment originates from a tunable laser. The pump light's Brillouin gain spectrum is used to amplify the phase modulation sideband. This amplification process is followed by the subsequent compression of the MPF's passband width by the narrow linewidth OEFL. The tunable optical delay line, in conjunction with pump wavelength adjustment, facilitates stable tuning for a cascaded single-passband MPF with an elevated Q-factor. High-frequency selectivity and a wide frequency tuning range are characteristics of the MPF, as evidenced by the results. click here At the same time, the bandwidth for filtering reaches a maximum of 300 kHz, exhibiting an out-of-band suppression exceeding 20 dB. The maximum Q-value is 5,333,104, and the range of tunable center frequencies is from 1 to 17 GHz. The cascaded MPF, as we propose it, excels not only in achieving a superior Q-value, but also in tunability, high out-of-band rejection, and robust cascading performance.

The utility of photonic antennas is undeniable in applications spanning spectroscopy, photovoltaics, optical communication systems, holography, and sensor design. Metal antennas, despite their compact size, often present challenges in their integration with CMOS technology. click here Si waveguides can be more readily coupled with all-dielectric antennas, but at the cost of a greater overall antenna size. click here This research paper outlines the design of a high-performance, small-sized semicircular dielectric grating antenna. The key size of the antenna measures a mere 237m474m, while emission efficiency surpasses 64% across the 116 to 161m wavelength spectrum. A novel, to the best of our knowledge, antenna-based approach enables three-dimensional optical interconnections among differing levels of integrated photonic circuits.

A novel approach to achieving structural color modulation on metal-coated colloidal crystal surfaces is presented, whereby a pulsed solid-state laser, and varying scanning rates, are employed. Different stringent geometrical and structural parameters are essential for achieving vibrant cyan, orange, yellow, and magenta colors. This research explores how laser scanning speeds and polystyrene particle sizes affect optical properties, and further analyzes how these properties vary with the angle of incidence. The reflectance peak's redshift is progressively pronounced as the scanning speed is increased, ranging from 4 mm/s to 200 mm/s, with 300 nm PS microspheres in use. Experimental studies also consider the influence of the microsphere particle's size and the angle at which the particles are struck. In PS colloidal crystals of 420 and 600 nm, two reflection peak positions displayed a blue shift corresponding to a deceleration in laser pulse scanning speed from 100 mm/s to 10 mm/s and an augmentation of incident angle from 15 to 45 degrees. Green printing, anti-counterfeiting, and other related applications benefit from this crucial, low-cost research undertaking.

A new, to the best of our knowledge, all-optical switch concept, leveraging the optical Kerr effect within optical interference coatings, is demonstrated. A novel approach to self-induced optical switching is facilitated by the internal intensity enhancement within thin film coatings, as well as the incorporation of highly nonlinear materials. The design of the layer stack, along with suitable material selection and the analysis of switching behavior of the manufactured parts, are all covered in the paper. Achieving a 30% modulation depth opens the door for subsequent mode-locking applications.

Thin-film deposition procedures have a minimum temperature threshold, dependent on the chosen coating technology and coating duration, which is frequently higher than room temperature. Subsequently, the management of thermally delicate materials and the adaptability of thin-film morphologies are confined. Therefore, low-temperature deposition processes, for factual reasons, demand active substrate cooling. The research focused on the correlation between low substrate temperatures and the attributes of thin films deposited by ion beam sputtering. SiO2 and Ta2O5 films, produced at 0°C, show a pattern of diminishing optical losses and increasing laser-induced damage thresholds (LIDT), in contrast to those grown at 100°C.