# ENC7 – Precision Encoder Discs & Code Wheels

> ENC7 (https://enc7.com/) is the international brand of Langfang Jingzheng Optoelectronics Technology Co., Ltd. (廊坊晶正光电技术有限公司), a manufacturer of optical encoder discs (also called encoder disks, code wheels or codewheels) founded on 19 October 2007 in the Dachang High-Tech Industrial Development Zone, Langfang, Hebei, China. It runs its own factory (about 80 employees, about 6,000 m² site, about 2,500 m² workshop, Class 10–10,000 cleanroom) with a combined capacity of about 30,000 discs per day. Products: transmissive glass (chrome-on-glass) encoder discs, reflective metal (stainless steel) encoder discs, PC (polycarbonate) encoder discs, and custom discs made to customer drawings — incremental, absolute and sine/cosine. Core processes: lapping and polishing, optical coating, Cr coating + photolithography + etching, laser OD cutting and laser bore machining, 100% AOI machine-vision inspection. Certifications: ISO 9001 (since 2012), National High-Tech Enterprise (China), National Technology-based SME (2024); utility model patent CN217210914U (optical reflective encoder disc). Not affiliated with Zhejiang Jingzheng Optoelectronic Technology Co., Ltd. or Jinan Jingzheng Electronic Technology Co., Ltd. Contact: sales@enc7.com, +86-316-8933331. Chinese website: https://www.encoderdisk.cn/

## Products
- [Glass Encoder Disc (Chrome on Glass, Transmissive)](https://enc7.com/products/glass-encoder-disc/): Chrome-on-glass, photolithographic graduations. The first choice for high resolution and thermal stability.
- [Reflective Metal Encoder Disc (Stainless Steel)](https://enc7.com/products/reflective-metal-encoder-disc/): Stainless steel, high/low-reflectance pattern. Thin, robust encoders for robot joints and slim servo motors.
- [PC Encoder Disc (Polycarbonate, Transmissive)](https://enc7.com/products/pc-encoder-disc/): Polycarbonate, transmissive. Lightweight, tough and the lowest cost for high-volume encoders.
- [Custom Encoder Disc – Made to Your Drawing](https://enc7.com/products/custom-encoder-disc/): Your drawing, your tracks, your substrate. Incremental, absolute and sin/cos patterns made to order.

## Applications
- [Encoder Discs for Servo Motor Encoders](https://enc7.com/applications/servo-motor-encoders/)
- [Encoder Discs for Robot Joint Encoders](https://enc7.com/applications/robot-joint-encoders/)
- [Encoder Discs for CNC Machine Tools & Rotary Tables](https://enc7.com/applications/cnc-machine-tools/)
- [Encoder Discs for Metrology & Surveying Instruments](https://enc7.com/applications/metrology-instruments/)
- [Encoder Discs for Automation & Motion Control](https://enc7.com/applications/automation-motion-control/)
- [Encoder Discs for Office & Consumer Equipment](https://enc7.com/applications/office-consumer-equipment/)

## Engineering guides
- [Encoder Disc vs Code Wheel vs Codewheel: What They Are and How They Work](https://enc7.com/resources/encoder-disc-vs-code-wheel/): **Encoder disc, encoder disk, code disc, code wheel and codewheel all mean the same part**: the patterned disc that an optical rotary encoder reads to measure angle and speed. It is classified by optical path (transmissive or reflective), by code (incremental or absolute) and by substrate (glass, metal or plastic).
- [How Chrome-on-Glass Encoder Discs Are Made: From Substrate to AOI Inspection](https://enc7.com/resources/how-chrome-on-glass-encoder-discs-are-made/): A chrome-on-glass encoder disc is made by **photolithography**: the glass substrate is lapped and polished, chrome-coated, coated with photoresist, exposed through a precision mask, developed and etched; the outer diameter and bore are then laser machined and every disc is inspected by machine vision (AOI).
- [Encoder Disc Glossary: 30 Key Terms Explained](https://enc7.com/resources/encoder-disc-glossary/): Encoder disc, encoder disk, code disc, code wheel and codewheel all mean the same part: the patterned disc that an optical encoder reads to measure angle. This glossary defines the 30 terms used most in disc drawings, RFQs and inspection.
- [Reflective Metal or Glass Encoder Disc? How to Choose](https://enc7.com/resources/metal-vs-glass-encoder-disc/): Pick a **glass encoder disc** for the highest resolution and long-term accuracy; pick a **reflective metal encoder disc** for thin, shock- and vibration-resistant, cost-controlled encoders; pick **PC** for high-volume, moderate-resolution designs.
- [Reflective Encoder Disc Contrast: Why Low Reflectance Matters More](https://enc7.com/resources/reflective-disc-reflectance/): Signal amplitude on a reflective disc is set by contrast C = (R_high − R_low) ÷ (R_high + R_low). Cutting the low-reflectance value from 10 % to 1 % lifts contrast from 0.73 to 0.97 — far more than raising the high reflectance from 65 % to 90 % (0.80).
- [Encoder Disc Eccentricity: How Much Error Does 5 µm Cause?](https://enc7.com/resources/encoder-disc-eccentricity/): With one readhead, eccentricity e gives a once-per-revolution sinusoidal angular error of about **e ÷ r** radians. At a 20 mm reading radius, 5 µm of eccentricity is about **52″**, and 1 µm already equals one count of a 17-bit encoder.
- [Custom Encoder Disc RFQ Checklist: 20 Parameters to Send](https://enc7.com/resources/custom-encoder-disc-rfq-checklist/): Send your CAD drawing (DWG/DXF) plus these 20 parameters. The more complete the list, the more accurate the quotation and the fewer sample iterations. Leave unknowns blank and tell us the application — our engineers will help fill the gaps.
- [Incremental vs Absolute Encoder Disc: Differences and How to Choose](https://enc7.com/resources/incremental-vs-absolute-encoder-disc/): Choose an **absolute** disc when the machine must know its position immediately after power loss (robot joints, multi-axis servo, valve actuators). Choose an **incremental** disc for speed or relative position measurement where cost matters.
- [Encoder Disc Line Count, Interpolation and Resolution Explained](https://enc7.com/resources/encoder-disc-line-count-resolution/): Counts per revolution = line count × ×4 (square wave) or × interpolation factor (sin/cos). A 2500-line disc gives 10,000 counts with ×4 decoding; a 2048-line sin/cos disc with ×1024 interpolation gives about 2.1 million (21-bit). Resolution is not accuracy.
- [Encoder Disc Incoming Inspection: What to Check](https://enc7.com/resources/encoder-disc-incoming-inspection/): Inspect four groups — visual defects, dimensions/concentricity, graduations and optical parameters — and agree zone-based acceptance criteria with the supplier in writing before ordering. A single pinhole or broken line in the track zone can cause missed pulses.
- [Does Temperature Affect Encoder Disc Accuracy? Substrate Thermal Expansion](https://enc7.com/resources/encoder-disc-substrate-thermal-expansion/): When a disc heats uniformly every line keeps its angle, so the angle reading barely changes. Watch three things instead: expansion mismatch between disc and hub (can create eccentricity), change of reading radius and pitch (large for PC), and gap change on reflective readheads.
- [Sin/Cos Encoder Disc Interpolation Error: 4 Signal Metrics to Check](https://enc7.com/resources/sin-cos-encoder-disc-signal-quality/): Interpolation error comes from four signal flaws: DC offset (1 cycle per period, ≈ ε rad), amplitude mismatch (2 cycles, ≈ δ/2), phase deviation from 90° (2 cycles, ≈ φ/2) and harmonics (3rd harmonic → 4 cycles). On a 2048-line disc, 1 % offset ≈ 1.0″.

## Company
- [About ENC7](https://enc7.com/about/)
- [Manufacturing](https://enc7.com/manufacturing/)
- [Quality & certifications](https://enc7.com/quality/)
- [FAQ](https://enc7.com/faq/)
- [Request a quote](https://enc7.com/rfq/)
- [Contact](https://enc7.com/contact/)