How are FIBERPORT COLLIMATORS manufactured?

FIBERPORT COLLIMATORS (Fiber Port Collimators) Manufacturing Process 

FIBERPORT COLLIMATORS (fiber port collimators) are core interface devices in optical communication and precision optical systems. Their primary function is to efficiently connect fiber optic and free-space optical paths, converting the divergent Gaussian beam emitted from the fiber into a highly parallel collimated beam, or conversely, efficiently coupling spatial parallel beams back into the fiber. Their manufacturing process integrates multiple technologies such as precision optical processing, micro-nano assembly, and automated calibration, adhering to strict quality control standards throughout. This ensures the products have core advantages of low insertion loss, high stability, and high alignment accuracy, meeting the high-end application requirements of fiber communication, scientific research experiments, remote sensing detection, and other fields. 

I. Preparatory Work and Selection of Core Raw Materials 

The primary step in processing and manufacturing is the precise selection and pre-treatment of raw materials, which is the foundation for ensuring consistent product performance. All raw materials undergo multiple screenings and meet industrial-grade or higher standards. 

Core optical components: 

High transmittance optical glass (such as quartz glass) is selected to fabricate collimating lenses, including self-focusing lenses (G-LENS) and spherical lenses (C-LENS). The C-LENS controls the focal length by optimizing the end face curvature to meet the requirements of different wavelengths. The lens surface must undergo precise polishing to ensure the end face roughness is less than 0.1nm, free of scratches and stains. At the same time, anti-reflection films are coated according to the application scenarios to reduce light reflection loss and increase light transmittance. The optical fibers are single-mode (SM) or multi-mode (MM) pigtails, and the end faces can be ground into PC, UPC or APC (angled physical contact) types as required. The APC interface end face is ground to an 8° angle, and the angle tolerance must be strictly controlled to ensure the return loss is better than -60dB. 

Mechanical structure components: 

The adjusting tube, guide sleeve, lens mounting tube and other parts are processed with low thermal expansion coefficient materials (such as ceramics, Kovar alloy), to prevent structural deformation caused by temperature changes and ensure long-term stability of use; the adjusting tube and adjusting housing are connected by SM1 thread, with the thread pitch precisely controlled at 0.2mm. A support sleeve is set between the guide sleeve and the lens mounting tube to ensure smooth adjustment and no deviation. The adjustment clearance between each component is strictly controlled within the range of 0.005-0.015mm. 

Auxiliary materials: 

High-stability optical adhesives (353ND glue, UV305 glue) are selected for component fixation and sealing, featuring high-temperature resistance and anti-aging properties, ensuring no glue detachment or performance degradation of the product within the wide operating temperature range of -55℃ to 125℃. Additionally, wave springs, locking screws, guide pins and other auxiliary components are provided. Among them, the wave spring is designed without contact with the APC interface, ensuring that the lens installation cylinder can output an ideal collimated beam at different adjustment positions. 

After the pretreatment of raw materials is completed, they need to be inspected one by one under a high-power microscope to remove substandard products. Only after ensuring that all components meet the processing standards can they proceed to the next manufacturing stage. 

Precision Machining and Pre-treatment of Core Components 

This section focuses on the precise processing of collimating lenses, fiber pigtails, and mechanical components. Through specialized equipment and meticulous operations, it ensures that the dimensional accuracy and performance of each component meet the standards. The core processes include: 

Collimating Lens Processing 

Micro-nano processing technology is adopted to perform cutting, grinding and polishing on optical glass substrates. Firstly, the glass substrates are precisely cut into the preset dimensions by high-precision cutting equipment, with an error controlled within ±0.001mm. Then, multiple grinding processes are carried out to gradually refine the surface flatness of the lenses. 

Finally, a precise polishing process is applied to achieve an ultra-high smoothness of the lens surface. Meanwhile, the lens curvature is optimized through gray-scale lithography or molding methods to ensure that the focal length precisely matches the design requirements, with wavefront aberration ≤λ/10 (λ=632.8nm), and to meet the wide-band requirements from 350nm to 2300nm. After processing, the lenses are cleaned and dried to remove surface impurities and water stains, avoiding any impact on the quality of light beam transmission. 

II Fiber Tail Fiber Processing 

The core of processing optical fiber pigtails lies in end face grinding and cleaning: Firstly, the outer sheath and coating layer of the optical fiber are stripped to expose the core. Then, the end face of the optical fiber is polished using precision grinding equipment. The end face for PC/UPC interfaces is ground into a micro-spherical surface, while for APC interfaces, it is ground into an 8° bevel. 

The end face angle tolerance is strictly controlled at 101.79° ± 0.025° to ensure that the angle between the optical fiber end face and the collimating lens optical axis meets the preset requirements. After grinding, the end face of the optical fiber is precisely cleaned with a cotton swab dipped in alcohol to remove grinding debris and impurities, avoiding any impact on the optical coupling efficiency. At the same time, the mode field diameter of the optical fiber is inspected to ensure it complies with the corresponding specification standards. 

Machining of Mechanical Components 

The components such as the adjustment cylinder, lens mounting cylinder, and guide sleeve are machined from materials like ceramics and Kovar alloy through CNC precision machines. The dimensional accuracy and coaxiality of each component are strictly controlled. The top of the adjustment cylinder is integrally formed with an APC interface, and a guide pin is fixed inside the adjustment cylinder for positioning and guiding. 

The locking screws are made of anti-corrosion materials to ensure that after the adjustment is completed, the locking spring can be compressed, making the lens mounting cylinder in a locked state and preventing positional deviation. After all the mechanical components are processed, surface anti-corrosion treatment (such as gold plating) is carried out to enhance wear resistance and corrosion resistance, and at the same time, surface burrs are removed to ensure smooth assembly. 

III. Precision Assembly and Active Alignment Debugging 

Precision assembly and active alignment are the core processes in the manufacturing of FIBERPORT COLLIMATORS, directly determining the alignment accuracy and optical coupling efficiency of the products. The entire process is carried out in a 10,000-level cleanroom to prevent dust contamination. The core procedures are divided into three steps: 

Pre-installation and Initial Fixation 

First, perform the pre-installation of the collimating lens: Under a high-power microscope, inspect the surface condition of the lens to ensure there are no defects. Then, insert the self-focusing lens with its bevel facing inward into the glass tube. Apply 353ND adhesive at a point 2/3 of the distance from the right-angle plane. Rotate the lens until 1.2mm is exposed outside the glass tube. Apply UV305 adhesive at the junction and push it in to 1mm. After exposure to ultraviolet light for more than 20 seconds to cure, place it in an oven for baking (bake at 85°C for 1-2 hours, and at 110°C for 2-3 hours). After baking, check again for any adhesive leakage to ensure a firm and secure assembly without any looseness. Next, perform the pre-installation of the pigtail fiber: Clean the pigtail fiber and insert it into the other end of the glass tube. Mark the highest point of the lens and the lowest point of the pigtail fiber for easy alignment and adjustment in the subsequent process. 

Assembly of Metal Sleeves and Sealing with Supplementary Glue 

After cleaning, apply 353ND adhesive evenly inside the gold-plated metal tube and heat it on an 85℃ hot plate for 2 minutes. Then, apply a circle of 353ND adhesive evenly around the end of the glass tube that has been pre-installed with the lens and the tail fiber. Rotate the gold-plated metal tube and insert it from the lens end, ensuring that the adhesive is evenly distributed between the metal tube and the glass tube, and that both ends are flush. Wipe off the excess adhesive, then hang the collimator with its right angle plane facing up for baking (bake at 85℃ for 1 hour), then hang it upside down for baking for 3 minutes. Add a small amount of 353ND adhesive and bake again (bake at 85℃ for 1 hour and at 110℃ for 2 hours) to ensure the sealing performance and prevent water vapor and dust from entering the interior and affecting the performance. 

Active Alignment and Precise Debugging 

An active alignment and debugging of the collimator after assembly is carried out by using a six-dimensional adjustment platform (X/Y/Z translation + θx/θy/θz rotation), in conjunction with a beam analyzer and a CCD image recognition system. The collimator is fixed on the adjustment frame and a low-power visible alignment laser is connected. The Zθ adjuster of the adjustment cylinder is adjusted to drive the inclined plate to move, achieving fine adjustment of the optical axis. Meanwhile, a plane mirror is placed at the farthest and nearest ends of the working distance of the collimator. 

The distance between the tail fiber and the lens is adjusted to ensure that the insertion loss difference at the two points is less than 0.02 dB, ensuring the parallelism and stability of the collimated beam. For APC interface collimators, it is particularly necessary to ensure that the optical axis of the collimating lens intersects the center line of the APC connector at the fiber end face. This is confirmed by detecting the ellipticity of the light spot, which needs to be greater than 95% to ensure the beam quality meets the standard. After alignment is completed, UV305 glue is applied at the junction of the tail fiber and the glass tube. After being cured by ultraviolet light, it is baked again to lock the position of the component and prevent any shift during subsequent use. 

IV. Multi-dimensional Quality Inspection and Aging Tests 

To ensure that every FIBERPORT COLLIMATOR meets the factory standards, we have established a full-process quality inspection system. Through multi-dimensional testing and aging tests, we eliminate substandard products to guarantee the long-term stable operation of the products. The core inspection items include: 

Optical performance testing: 

A standard collimator is used to set up the testing optical path, and the positions of the mirror frame, standard focusing lens and camera are determined. After replacing the collimator to be tested, it is adjusted until the camera spot is the smallest. 

The spot size information is collected, and the divergence angle is calculated to determine if it is less than the theoretical divergence angle (calculation formula: 2θ1 = d2/f2 * 180/π, where d2 is the focused spot diameter and f2 is the focal length of the standard focusing lens). At the same time, insertion loss (≤0.3dB), return loss (APC interface ≥60dB, UPC/PC interface ≥50dB), and polarization-dependent loss (≤0.1dB) are tested to ensure that the optical performance meets the standards. 

Mechanical performance testing: 

Inspect the dimensional accuracy, coaxiality and assembly firmness of each component to ensure the smoothness of the adjusting cylinder's thread, the effectiveness of the locking screw, and the precise limit of the guide sleeve. Test the tensile load and anti-vibration and anti-shock performance of the product, which should meet the requirements of military standard GJB 150A. Under a vibration environment of 5-2000Hz and an acceleration of 5g, the performance change should be less than 0.1dB, and there should be no structural damage under mechanical shock conditions of 1000g and 0.5ms. 

Environmental adaptability and aging tests: 

The product is placed in a high and low temperature cycling chamber for temperature cycling tests ranging from -40°C to 85°C (industrial grade) and -55°C to 125°C (aerospace grade) (500 cycles), ensuring that the insertion loss change is less than 0.2 dB. A 1000-hour high-temperature and high-humidity test is conducted at 85°C/85% RH, with a performance degradation of less than 0.3 dB. Long-term aging tests (MTBF > 100,000 hours) are carried out to verify the long-term stability of the product, ensuring no performance degradation and no structural damage in complex working environments. 

Appearance and consistency inspection: 

Products are examined under a high-power microscope to ensure no scratches, no delamination, no stains, and clear markings. During mass production, performance parameters of a sample of products are spot-checked to ensure consistency between batches, with insertion loss fluctuation < 0.2 dB, to meet the requirements of customers for large-scale applications. 

All products that pass the inspection will be numbered, packaged, and equipped with a product inspection report before leaving the factory. Unqualified products will be disassembled, reworked or scrapped, with full traceability throughout the process to ensure the controllability of product quality. 

V. Customized Processing and Full-process Control 

To meet the individualized demands of various industries, we offer customized processing services for FIBERPORT COLLIMATORS. Based on the customer's wavelength requirements (350nm - 2300nm), interface types (standard interfaces such as SC/FC/LC), power carrying capacity (1mW - 1000W), and size specifications (miniaturization, lightweight), we optimize the lens design, mechanical structure, and assembly process to adapt to the application needs of different scenarios, including fiber optic communication, medical equipment, lidar, and scientific research experiments. 

The entire manufacturing process strictly adheres to the ISO 9001 quality management system and ISO 13485 medical certification standards (for custom products in medical scenarios). From raw material selection, component processing, assembly and debugging to quality inspection, detailed production records and traceability systems are established for each link to ensure stable product quality and reliable performance, providing customers with high-quality fiber port collimators and professional technical support.