Optical Sensor Tube Structure Reducing Side Lobes

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Optical sensors face reduced reliability due to side lobes in light beam profiles and structural complexity, which impairs object detection accuracy.

Innovation Solution

The optical sensor design incorporates a tube structure composed of multiple tube elements connected via flexible joints, allowing for easy integration of optical elements and optimization of optical properties, reducing side lobes and enhancing detection reliability with minimal manufacturing effort.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If optical units with lenses are used to shape and focus light beams, then object detection reliability is improved, but side lobes are generated that reduce detection reliability

Engineering Contradiction:
Improveobject detection reliabilityVSAvoidside lobes
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies this principle by using light-absorbing materials (black anodized surfaces, Vantablack coating, or carbon black paint) to convert the harmful parasitic reflections that create side lobes into beneficial light absorption. The tube elements are specifically designed with these light-absorbing surfaces to eliminate unwanted reflections while maintaining the useful light beam transmission.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent extracts and removes the harmful reflective surfaces from the optical path by replacing them with light-absorbing materials. The tube elements are designed to take out the parasitic reflections that occur within the housing and optical unit, eliminating the source of side lobes while preserving the main light beam functionality.

Inventive Principle:
Principle #2Taking out (Extraction)

2Ease of manufacture

If traditional housing designs are used for optical sensors, then manufacturing is simplified, but design complexity increases due to integration requirements

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoiddesign complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The patent divides the traditional monolithic housing into separate functional components: tube elements that can be individually manufactured and then assembled. Each tube element can be independently produced with specific optical properties (light-absorbing surfaces, aperture positions), and then joined together to form the complete housing structure. This segmentation allows for simpler individual manufacturing steps while reducing overall design complexity through modular assembly.

Inventive Principle:
Principle #1Segmentation

3Object-generated harmful factors

If light-absorbing materials are applied to tube elements, then side lobes are reduced, but manufacturing processes become more complex

Engineering Contradiction:
Improveparasitic reflectionsVSAvoidmanufacturing process complexity
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The patent changes the surface properties of the tube elements by applying light-absorbing coatings or using black anodized materials. This parameter change (surface optical properties) effectively reduces parasitic reflections and side lobes. The manufacturing complexity is managed by integrating this surface treatment into the tube element production process itself, making it a standard step rather than an additional complex process.

Inventive Principle:
Principle #35Parameter changes

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 design achieves high detection reliability with simplified manufacturing, effectively reducing optical interference and improving object detection accuracy in optical sensors.

Implementation Method 1

The tube has a light-absorbing surface. The light-absorbing surface is formed by a dark thermoplastic elastomer with a matte surface.

Methodology Applied
Scientific EffectLight absorption: Absorption (EM radiation)

Data Source

PatentEP4220239B1Optical sensor
Publication Date: 2024.12.25 LEUZE ELECTRONIC GMBH & CO KG
  • EP4220239B1 patent drawingFigure 1
  • EP4220239B1 patent drawingFigure 2~3
  • EP4220239B1 patent drawingFigure 4a~4b

AI summary

The invention relates to an optical sensor for detecting objects in a monitoring area, comprising at least one transmitter (4) emitting light beams (3) having an optical axis (A), and at least one receiver (6) having an optical axis (A) and configured to receive light beams (3). A tube (10) is associated with each transmitter (4) and receiver (6), the longitudinal axis of which extends in the direction of the optical axis of the transmitter (4) or receiver (6). The tube (10) consists of several tube elements (12a, 12b) that can be joined to the tube (10) transversely to the optical axis. The tube (10) forms at least one element plane in which an optical element is present. The tube (10) has one or more element planes in the form of aperture planes (14, 15), each containing an aperture (13).