Prism Illumination System for Imaging Scanner Light Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current imaging-based barcode scanners face inefficiencies in illumination systems, particularly in low ambient light conditions, with low light coupling efficiency and inconsistent illuminating line sharpness, which affects reader performance and increases costs due to reflective coatings.
Innovation Solution
Incorporating a coupling optical prism between the light source and illumination lens, featuring a first surface with an elongated section and a second section to define an aperture, and a third surface that reflects illumination light while preventing additional light from being projected onto the target, enhancing light throughput and consistency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a conventional illumination system is used without a coupling prism, then the device complexity is low, but the light coupling efficiency is low and the illuminating line sharpness is inconsistent
Solution Approach 1:
A coupling optical prism is introduced as an intermediary component between the illumination light source and the illumination lens. The prism mediates the light transmission by refracting and directing the light rays, improving the coupling efficiency between the light source and lens while maintaining a relatively simple overall system structure.
Solution Approach 2:
The illumination system transitions from a one-dimensional light path to a multi-dimensional optical path by incorporating the prism. The prism introduces additional optical dimensions through its multiple surfaces (first surface with aperture section, second surface, and third reflective surface), enabling better light control and coupling in multiple spatial directions.
2Illumination intensity
If reflective coatings are used to improve illumination performance, then the illumination intensity improves, but the manufacturing cost increases and mass production consistency deteriorates
Solution Approach 1:
The patent replaces expensive reflective coatings with a simple optical prism made of transparent material. The prism uses inherent optical properties (refraction and reflection at air-glass interfaces) rather than requiring costly reflective coatings, significantly reducing manufacturing cost while maintaining illumination performance.
Solution Approach 2:
The system changes the optical parameters by using a prism with specific geometric characteristics (elongated first section with length at least four times its width, third surface configured for reflection). These geometric parameter changes enable the prism to control light paths effectively without requiring reflective coatings, improving both cost and consistency.
3Productivity
If the first section on the first surface has a length at least four times as long as its width, then the light coupling efficiency improves, but the aperture size is reduced
Solution Approach 1:
The prism's first surface is divided into functionally distinct regions: a large elongated first section for light coupling and a smaller second section defining the aperture edge. This local differentiation allows the first section to maximize light collection efficiency while the second section controls the final aperture, optimizing both parameters simultaneously.
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 improves light coupling efficiency by at least two times, providing a brighter and sharper illumination line, enhancing reader performance under low ambient light conditions without the need for reflective coatings, thus reducing costs and improving mass production consistency.
Implementation Method 1
The third surface of the prism is configured to reflect the illumination light received from the first section onto the second surface to redirect at least a portion of the illumination light received from the first section to pass through both the second surface of the prism and the illumination lens
Implementation Method 2
pass through both the second surface of the prism and the illumination lens for projecting the portion of the illumination light onto the target object within the imaging field of view
Data Source
AI summary
An apparatus includes an illumination lens, an illumination light source for generating illumination light, and a prism made of optical transparent material. The first section on the first surface of the prism has a length that is at least four times as long as its width. The first surface of the prism includes a second section adjacent to the first section for defining the edge of an aperture. The third surface of the prism is configured to reflect the illumination light received from the first section onto the second surface of the prism. At least a portion of the illumination light received from the first section passes through both the second surface of the prism and the illumination lens for projecting illumination light onto a target object within an imaging field of view.