What Seikoh Giken does

Seikoh Giken (株式会社 精工技研), founded in 1972 and publicly listed on the Tokyo Stock Exchange (TYO:6834), is a Japan-based precision optical technology company headquartered in the Kamakura/Fujisawa area of Kanagawa Prefecture. The company designs and manufactures optical communication components (connectors, ferrules, adapters, attenuators), fiber optic manufacturing equipment (SFP-560A polishing machines, SFPS-V2 automatic polishing systems, FAIS and D-Scope inspection instruments), consumables (polishing films, pads, cleaners), RF-over-Fiber (A-RoF) transmission units, Power-over-Fiber (PWoF) systems, optical E-field sensors (OEFS), and precision molded lenses including glass-resin hybrid (MSG), liquid injection molded (LIM), and diffractive optical elements (DOE). Its products serve telecommunications carriers, data center operators, broadcasters, 5G infrastructure providers, EMC testing facilities, automotive tier-1 suppliers, vehicle manufacturers (Toyota HiAce via Tokai Rika), and medical device manufacturers.

Revenue is generated primarily through direct hardware sales of customized components, equipment, and consumables. The company's flagship optical production factory, Hangzhou Seikoh Giken in China, is undergoing automation upgrades for capacity expansion, and additional subsidiaries include Fuji Electronics (Japan), Data-Pixel SAS (France), and MG Japan. Strategic co-development partnerships span Sumitomo Heavy Industries (SSIMC in-mold coating, targeting 2026 commercialization), Tokai Rika (in-mold coating for Toyota HiAce interior switch parts), Chuo University and AIST (5G 28GHz optical E-field sensor), and IIJ (GNSS timing synchronization thought leadership).

The go-to-market model is exclusively direct: trade show participation (OFC, ECOC, Inter BEE, COMNEXT, Interop Tokyo, OPIE, 3DECO tech), co-hosted technical seminars (GNSS TimeSync 2025), segmented phone-based sales lines by product category, and website inquiry forms. No distributor, reseller, or e-commerce channels are used. Pricing is quote-based and not publicly disclosed. The company's competitive positioning rests on a global patent portfolio covering its proprietary self-rotation/revolution fiber polishing mechanism, proprietary A-RoF/PWoF/OEFS optical transmission technologies, and vertically integrated precision manufacturing spanning mold design through optical component assembly.

Name

Seikoh Giken

Legal name

株式会社 精工技研

Website

https://seikoh-giken.co.jp

Company type

Private

Founded year

1972

Operating status

Operating

Headcount range

501–1,000 employees

Short description

Seikoh Giken is a Japan-based precision optical technology company that designs and manufactures optical communication components, fiber optic polishing and inspection equipment, RF-over-Fiber and Power-over-Fiber systems, optical electric field sensors, and precision molded lenses for telecommunications, data centers, broadcasters, 5G, automotive, EMC testing, and medical device customers.

Ownership category

akta.pro rank

Product category

Optical Components & Equipment

SIC

Optical Instruments & Lenses (3827), Search, Detection, Navagation, Guidance, Aeronautical Sys (3812)

akta.pro primary industry

Optoelectronic Components (LEDs, photodiodes, optocouplers, optical sensors) (IMAGAJAF)

akta.pro secondary industries

Injection Molded Optical & Transparent Parts (Lenses, Light Guides) (IMANAFAL), Optical & Light Sensors (Photodiodes/ALS/Color/UV) (HDAHALAE), Optoelectronic Receivers & Transceivers (Photodetectors/Optical Modules) (HDAHALAM), Machine Vision & Optical Sensing (Cameras, 3D vision, LiDAR, illumination) (IMAGAFAB)

Keywords

• Optical fiber connectors
• Fiber optic polishing equipment
• RF-over-Fiber transmission
• Precision optical lenses
• Optical E-field sensors

Headquarters

HQ city

Matsudo

HQ country

Japan

HQ region

Asia

Offices5 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Supply Chain, Operations, Technology or R&D, Infrastructure, Marketing or Sales

Revenue model

1. Optical Communication Components & Equipment: Manufacture and sale of optical fiber connectors (LC Uniboot, MPO/MT), ferrules, adapters, attenuators, optical packaging components, and fiber assembly tools. Revenue generated through direct sales of precision optical components to telecommunications carriers, data center operators, and network equipment manufacturers.
2. Optical Manufacturing Equipment: Sale of fiber optic polishing machines (SFP-560A series, OFL-15A), polishing consumables (films, pads), polishing holders, end-face inspection systems (FAIS, D-Scope), cleaners (Ferrule Pro SPR series, Handi Mate), and measurement instruments (DAISI, KONCENTRIK). Consumables and replacement parts provide recurring revenue from existing equipment installed base.
3. Precision Molding & Decoration (Automotive & Medical): Precision injection molding products including automotive components (switches, interior parts) using SSIMC in-mold coating technology, medical/biotech molded parts, and DOE/Hybrid lenses. Revenue from custom-part manufacturing under long-term supply agreements with tier-1 automotive suppliers and medical device manufacturers.
4. RF-Over-Fiber & Optical Sensing Systems: RF光伝送 units, GNSS optical transmission units, optical E-field sensors, noise measurement optical sensors, and PWoF systems sold to broadcasters, defense/EMC testing facilities, and telecommunications companies. Custom system integration and engineering services for specific application deployment.
5. Custom Optical Lenses: Reflow-resistant MSG hybrid lenses, LIM ultra-small lenses, DOE elements, and far-infrared lenses for cameras, 3D sensing modules, medical endoscopes, and industrial sensing applications. Revenue from custom-designed, application-specific lens products.

Go-to-market motion1 record

Distribution channels4 records

Marketing channels8 records

Core offering

Seikoh Giken manufactures and sells precision optical fiber components (connectors, ferrules, adapters, attenuators), fiber optic manufacturing equipment (polishing machines, end-face inspection systems, cleaners), RF-over-Fiber (A-RoF) and Power-over-Fiber (PWoF) optical transmission devices, optical E-field sensors for EMC and 5G measurement, and hybrid glass-resin lenses (MSG, LIM, DOE) for camera and 3D sensing modules. The company also produces precision molded parts and SSIMC in-mold coating systems for automotive and medical applications.

Product overview

Seikoh Giken (株式会社精工技研) is a precision optical technology company offering a comprehensive portfolio of optical communication components and manufacturing equipment. The core product lines include: (1) Optical communication components such as LC/MT connectors, ferrules, adapters, and attenuated connectors for data centers and telecommunications; (2) Fiber optic manufacturing equipment including the SFP-560A series automatic polishing machines and SFPS-V2 multi-fiber polishing systems; (3) Endface inspection systems (FAIS/D-Scope) and cleaning equipment (SPR-3, Handi Mate series) for quality control in connector manufacturing; (4) RF over Fiber (A-RoF) transmission devices and Power over Fiber (PWoF) systems for broadcasting and communication infrastructure; (5) Optical electric field sensors (OEFS) for EMC testing and 5G applications; (6) Reflow-compatible hybrid lenses (MSG, LIM types) and diffractive optical elements (DOE) for camera modules and 3D sensing; and (7) Precision measurement instruments including interferometers and eccentricity meters. The company also provides precision molding and processing services for automotive, medical, and optical device applications.

Differentiator

Problem solved

Functional benefit

Brands

• A-RoF (RF over Fiber): RF optical transmission technology that transmits radio waves in their original form through optical fiber
• PWoF (Power over Fiber)
• MSG Lens (Multiple complex Super Glass)
• LIM Lens (Liquid Injection Mold)
• DOE (Diffractive Optical Element)
• Handi Mate
• Ferrule Mate
• Ferrule Pro
• FAIS (Fiber Auto Inspection System)
• D-Scope

Products and services

• Optical Fiber Connectors Optical fiber connectors including LC Uniboot Intelli-Cross Pro, SC, FC, and MT/MPO types for telecommunications and data center applications, available in various configurations to enable reduced cable footprint and improved management.
• Ferrules Precision ferrules for optical fiber connections, critical components ensuring accurate alignment and low insertion loss in telecommunications and data center infrastructure.
• Optical Adapters Optical fiber adapters for connecting and aligning fiber optic connectors in telecommunications infrastructure.
• Plug-Type Fixed Attenuators Optical attenuators for controlling signal strength in fiber optic networks.
• SFP-560A Series Polishing Machine Mass-production optical fiber polishing machine featuring proprietary DPC (DPC: Dual Pressure Control) technology for precise polishing pressure control, with the proprietary self-rotation/revolution mechanism supporting up to 72 ferrules simultaneously with parallel processing capability.
• SFPS-V2 Automatic Polishing System Multi-fiber compatible automatic polishing device for fiber optic connectors, featuring fully automated polishing pad handling and ferrule endface cleaning. Supports multi-core ferrules including LC/PC 72-axis and MT/APC 36-axis configurations.
• FAIS (Fiber Auto Inspection System) Automated optical connector endface inspection system achieving automatic positioning, centering, focusing, and PASS/FAIL judgment based on IEC standards for scratches and pits.
• D-Scope Endface Inspection Device Production-line optical fiber endface microscope by Data-Pixel featuring deep blue LED and Kohler illumination for uniform visibility and inspection reproducibility, with various magnification options.
• SPR-3 Ferrule Pro Cleaning System High-speed production-line endface cleaner for multi-core ferrules and connectors (MT/MPO) achieving 3-second cleaning cycle per connector with dual-action mechanism and optimized solvent.
• SHM-503 Handi Mate Cleaning Tool Handheld optical connector endface cleaner with 500+ cleaning cycles, supporting SC, FC, LC, MU, ST single-core PC and APC connectors.
• SFM2.0 Ferrule Mate Cleaner Ferrule endface cleaner featuring unique cloth feed and rotation mechanism for efficient cleaning of ferrules in adapters, supporting 800+ cycles (MPO: 500+ cycles).
• RF Optical Transmission Units (A-RoF) RF over Fiber technology enabling transmission of RF signals (9kHz to 60GHz+) through optical fiber with low loss (0.2dB/km), noise immunity, and low latency. Products include GNSS, 1PPS, 10MHz, millimeter-wave, TV, and FPU transmission units.
• Power over Fiber (PWoF) System Optical power transmission technology using high-intensity laser light transmitted through fiber optic cable and converted to electrical power via photodiodes. Achieves complete electrical isolation and immunity to lightning/EMP, with practical transmission exceeding 3km (SMF specification) and up to 20W power delivery per fiber.
• Optical E-Field Sensors (OEFS) Electric field sensors using electro-optic effect for measuring electromagnetic fields without disturbing the field. Non-metallic sensor heads with fiber optic transmission enable ground-separated accurate measurements for EMC testing, radar pulse measurement, and HEMP applications. Standard products cover ~10GHz; custom versions available for ultra-strong fields, ultra-compact, and 5G 28GHz bands.
• 5G 28GHz Band Optical E-Field Sensor 5G-focused optical electric field sensor developed jointly with Chuo University and AIST, supporting 27-29.5GHz frequency range with minimum measurable field strength of 0.03V/m at 28GHz.
• ES-3 Series Noise Measurement Optical Sensors Optical sensors for measuring electric field and voltage noise during immunity testing of electronic equipment, particularly suitable for wideband high-power ESD testing near field measurement.
• MSG (Multiple complex Super Glass) Hybrid Lens Glass-resin hybrid lens combining glass strength and environmental resistance with aspheric shaping via UV-curable resin. Heat-resistant up to 260°C reflow process, suitable for small camera modules and 3D sensing modules.
• LIM (Liquid Injection Mold) Lens Liquid injection molding lens using thermosetting resin for ultra-small lenses as small as φ1mm with thickness 0.1mm or less, ideal for 3D sensing modules and disposable medical endoscopes.
• DOE (Diffractive Optical Element) Diffractive optical elements using 3D microstructure pattern formation on glass substrates (sub-1μm precision) for laser beam shaping into various projection patterns, applied in 3D sensing applications.
• Far-Infrared Lenses Ultra-precision aspheric processing technology for far-infrared lenses using hard-brittle materials (silicon, germanium, sapphire) for security cameras, thermography, gas sensors, and liquid analysis equipment.
• DAISI-V3 Interferometer Digital Automated Interferometer for Surface Inspection with auto-focus, auto-calibration, and automatic connector holding for high-speed single-ferrule endface shape measurement.
• DAISI-MT V3 Multi-Fiber Interferometer Multi-fiber connector endface shape measurement interferometer with megapixel CCD for high reproducibility and fast measurement.
• KONCENTRIK V2 Eccentricity Meter Eccentricity measurement instrument for patch cord core eccentricity and ferrule hole eccentricity with approximately 10-second measurement speed.
• IPC (Independent Pressure Control) Polishing Holders Individual ferrule pressure application holders ensuring consistent polishing quality regardless of ferrule length variation, supporting 1-40 axis polishing.

Quantifiable outcome

• Reflow resistance of 260–265°C for MSG hybrid lenses, compatible with standard SMT reflow processes
• +4 more outcomes

Named customers8 records

Segments4 records

Ideal customer profiles7 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature7 records

Partnerships

Eight partnerships are on record, tiered core and minor.

• Sumitomo Heavy Industries (住友重機械工業株式会社)coreStrategic or Co-development Partner · 17 September 2025Co-development of environmentally conscious in-mold decoration technology 'SSIMC' (型内塗装システム). The jointly developed SSIMC system enables in-mold painting during injection molding, eliminating post-molding spray painting steps. This reduces power consumption, CO2 emissions, and VOC emissions. Target commercialization and system sales in 2026. This is a flagship co-development addressing environmental sustainability in automotive component manufacturing.
• Tokai Rika (株式会社東海理化)coreStrategic or Co-development Partner · 8 April 2025Joint development of Japan's first in-mold coating technology specifically for small automotive components. This technology was applied to switch components in Toyota's 'HiAce' vehicle — marking the first adoption of this type of technology for small components in Japan (company research). The partnership leverages Seikoh Giken's precision molding expertise combined with Tokai Rika's automotive component manufacturing capabilities.
• Chuo University (三重大学)coreTechnology or IntegrationIndustry-government-academia joint development partner for the 5G 28GHz band optical E-field sensor (OEFS for 5G). The sensor was jointly developed by Seikoh Giken, Chuo University, and the National Institute of Advanced Industrial Science and Technology (AIST).
• National Institute of Advanced Industrial Science and Technology / AIST (産業技術総合研究所)coreTechnology or IntegrationJoint development partner with Seikoh Giken and Chuo University for the 5G 28GHz band optical E-field sensor. AIST contributes research institute capabilities and measurement science expertise for the development of specialized electro-optic sensor technology for 5G frequency bands.
• Hangzhou Seikoh Giken (杭州精工技研有限公司)coreOthersConsolidated subsidiary and flagship production factory for optical products located in Hangzhou, China. Significantly expanded production capacity through automation upgrades. Serves as primary manufacturing base for optical components for the Japanese and international markets.
• Fuji Electronics (不二電子工業株式会社)minorOthersRelated company within the Seikoh Giken group network. Fuji Electronics operates as an associated entity within the corporate group structure.
• MG Japan (株式会社エムジー)minorOthersRelated company within the Seikoh Giken group network. Operates as an associated entity within the broader corporate group.
• Internet Initiative Japan / IIJ (インターネットイニシアティブ)minorGTM or Marketing PartnerIIJ is the organizer of the GNSS TimeSync 2025 technical seminar, which Seikoh Giken co-hosted and presented at. This represents a joint marketing/thought leadership collaboration positioning Seikoh Giken in the GNSS timing synchronization market segment.

Scale indicators4 records

Recent moves6 records

Expansion highlights6 records

Broad incumbents

• Furukawa Electric: Furukawa Electric manufactures optical fiber, cables, and related components for telecom and data-center applications. Comparable as a Japanese incumbent in fiber-optic infrastructure with broader exposure to metals and electronics, but not a direct competitor in Seikoh Giken's specialty connector/ferrule and polishing-equipment niches.
• Fujikura: Fujikura manufactures optical fiber, cables, and connectivity products for telecom and electronics. A broad Japanese incumbent operating in adjacent fiber-optic categories, but lacking Seikoh Giken's specialization in precision fiber-polishing equipment and optical E-field sensors.
• Sumitomo Electric Industries: Sumitomo Electric is a major Japanese manufacturer of optical fiber, cables, and components, and is also Seikoh Giken's SSIMC co-development partner. Comparable as a broad incumbent in fiber-optic infrastructure, though much larger and more diversified across wire harness, industrial, and materials businesses.

Direct peers

• Lumentum Holdings: Lumentum designs and manufactures optical and photonic products including connectors, lasers, and components for telecom, data center, and 3D sensing. Directly comparable to Seikoh Giken in optical communications components and 3D-sensing photonics, though Lumentum operates at materially greater scale.
• Yokowo: Yokowo manufactures precision components including connectors and electromagnetic devices across automotive, semiconductor test, and communications markets. Comparable in Japanese precision-component manufacturing with similar automotive and connectivity customer adjacencies.
• Coherent (formerly II-VI): Coherent produces optoelectronic components, laser systems, and optical materials serving communications, industrial, and semiconductor end markets. A direct peer in photonic and optical-component design, with broader vertical integration across materials and laser subsystems.
• Senko Advanced Components: Senko manufactures fiber optic connectors, adapters, and interconnect components for data centers and telecom networks. Directly competes with Seikoh Giken in LC/MPO connectors and ferrule products for hyperscale and enterprise fiber deployments.
• T&S Communications: T&S Communications manufactures fiber optic polishing equipment, inspection systems, and connector-related tooling. Directly competes with Seikoh Giken's SFP/SFPS polishing machine and FAIS/D-Scope end-face inspection product lines for connector manufacturers worldwide.
• Santec Corporation: Santec designs and manufactures optical components, tunable lasers, and test/measurement instruments for telecom and sensing. Directly comparable to Seikoh Giken's optical-sensing and measurement-instrument product lines (DAISI, OEFS, etc.), at a similar Japanese mid-cap scale.
• Adamant Namiki: Adamant Namiki produces precision optical components, jewel bearings, and miniature motor parts. Comparable as a Japanese specialty manufacturer of optical and high-precision components serving medical, semiconductor, and communications markets.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• Facebookfacebook.com/seikohgikencompany
• LinkedInlinkedin.com/company/seikoh-giken-co.-ltd.

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Subsidiaries4 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Seikoh Giken