Optical Disc Drive Shielding via Ground Pattern Contact
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical disc drive devices face challenges in reducing noise radiation from wiring lines used for signal transmission and reception between the internal unit and external electronic equipment, which is not effectively addressed by conventional metallic exterior casings.
Innovation Solution
The optical disc drive device features a metallic exterior casing with a printed wiring substrate that includes a connector for signal transmission and reception, where the substrate has a ground pattern surrounding the connector, and the fringe portion of the casing opening is in electrical contact with the ground pattern, effectively reducing noise radiation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a metallic exterior casing is used for housing the internal unit, then dust prevention and shielding of outward radiation noise are improved, but noise radiated from wiring lines between the internal unit and external electronic equipment is not effectively reduced
Solution Approach 1:
A ground pattern is introduced as an intermediary element between the connector and the metallic exterior casing. This ground pattern acts as a mediator to shield the wiring lines from noise radiation, effectively reducing the harmful electromagnetic interference while maintaining the shielding function of the metallic casing.
Solution Approach 2:
The solution combines the metallic exterior casing with a ground pattern formed on the printed wiring substrate, creating a composite shielding structure. This composite approach integrates the advantages of both the metallic casing (mechanical strength and basic shielding) and the ground pattern (electromagnetic interference shielding for wiring lines).
2Ease of operation
If the connector is exposed outside through an opening in the exterior casing, then transmission and reception of electrical signals are improved, but noise radiation from wiring lines increases
Solution Approach 1:
The ground pattern serves as an intermediary shielding element positioned between the exposed connector and the external environment. It allows the connector to remain exposed for electrical signal transmission while simultaneously providing electromagnetic shielding to reduce noise radiation from the wiring lines.
Solution Approach 2:
The ground pattern is locally positioned around the connector area where noise radiation occurs, providing targeted electromagnetic shielding exactly where needed. This localized approach does not interfere with the connector's exposure for signal transmission but effectively addresses the noise issue at its source.
3Object-generated harmful factors
If the ground pattern is formed to surround the connector, then noise radiation is reduced, but device complexity increases
Solution Approach 1:
The ground pattern is merged with the printed wiring substrate, combining the shielding function with the existing electrical connection structure. This integration eliminates the need for separate shielding components, reducing overall device complexity while maintaining effective noise radiation reduction.
Solution Approach 2:
The ground pattern serves multiple functions simultaneously: it provides electromagnetic shielding to reduce noise radiation, establishes electrical connection to the metallic casing, and structurally supports the connector area. This multi-functionality reduces the need for additional separate components, simplifying the overall device structure.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration significantly reduces noise radiation from the wiring lines, enhancing the shielding effectiveness and maintaining electrical connectivity even in downsized devices.
Implementation Method 1
a fringe portion of the opening of the exterior casing and the ground pattern are in electrical contact with each other
Implementation Method 2
the printed wiring substrate has a ground pattern formed to surround the connector... effectively reducing noise radiation
Data Source
AI summary
An optical disc drive device has a metallic exterior casing and an internal unit to be housed in the exterior casing. The internal unit further includes an optical pickup unit for performing recording or reproduction of information signals on an optical disc, and a printed wiring substrate on which a connector electrically connected to the optical pickup unit and serving for transmission and reception of electrical signals from and to external electronic equipment is mounted. The exterior casing has an opening for allowing the connector to be exposed outside, the printed wiring substrate has a ground pattern formed to surround the connector, and a fringe portion of the opening of the exterior casing and the ground pattern are in electrical contact with each other. Thus, radiation noise from around wiring lines contained in the optical disc drive device or the like is reduced.