Red-Lens Vehicle Lamp for Wavelength-Selective Light Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle lamps using secondary light sources struggle to meet vehicle regulations regarding the outgoing light emitted from the lamp lens.
Innovation Solution
The vehicle lamp design includes a lamp housing and lens, an excitation-light irradiation unit with an excitation light source and final irradiation surface, and a light conversion unit with a light emitting film, reflection film, and secondary-light emitting surface. The excitation light has a dominant wavelength shorter than 500 nm, and the secondary light has a dominant wavelength longer than 500 nm, with the lamp lens being a red lens that transmits 80% or more of the secondary light while absorbing 10% or less of the excitation light.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a light emitting layer is used to convert excitation light to secondary light, then surface light emission is achieved and reliability is improved, but the outgoing light from the lamp lens may not satisfy vehicle regulations due to insufficient wavelength separation
Solution Approach 1:
The patent applies parameter changes by selecting specific dominant wavelengths for the excitation light (shorter than 500 nm) and secondary light (longer than 500 nm), and by designing the red lens with specific transmittance characteristics (10% or less for excitation light, 80% or more for secondary light). This wavelength parameter separation ensures that the outgoing light satisfies vehicle regulations while maintaining the reliability benefits of the light emitting layer.
2Productivity
If the lamp lens transmits more secondary light, then the light output efficiency is improved, but more excitation light may also be transmitted causing regulation non-compliance
Solution Approach 1:
The red lens is designed with local quality in terms of wavelength-selective transmittance. It has high transmittance (80% or more) for the secondary light wavelength region while having low transmittance (10% or less) for the excitation light wavelength region. This allows the lens to efficiently transmit the desired secondary light while blocking the harmful excitation light, thus improving light output efficiency without causing regulation non-compliance.
Solution Approach 2:
The patent utilizes color changes through the red lens that selectively transmits red light (secondary light with dominant wavelength longer than 500 nm) while absorbing or blocking blue/violet light (excitation light with dominant wavelength shorter than 500 nm). This color-selective property enables the lens to transmit secondary light efficiently while preventing excitation light transmission, resolving the contradiction between productivity and harmful factors.
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 ensures that the outgoing light emitted from the lamp lens satisfies vehicle regulations, with the red lens effectively transmitting the secondary light while minimizing the emission of excitation light.
Implementation Method 1
the light emitting film emits secondary light by the excitation light emitted from the excitation-light final irradiation surface
Implementation Method 2
the lamp lens is constituted by a red lens... in which transmittance of the excitation light is 10% or less in a wavelength region of the excitation light and the transmittance of the secondary light is 80% or more in a wavelength region of the secondary light
Implementation Method 3
a reflection film that reflects the secondary light emitted from the light emitting film toward the light emitting film side
Data Source
AI summary
A vehicle lamp includes a lamp housing with a red lens forming a lamp chamber, an excitation-light irradiation unit for emitting excitation light with a wavelength shorter than 500 nm, and a light conversion unit disposed in the lamp chamber. The lamp lens is a red lens. The light conversion unit includes a light emitting film that receives the excitation light and emits secondary light of a wavelength longer than 500 nm, a reflection film for redirecting the secondary light towards the light emitting film. The secondary light exits the vehicle lamp through the red lens.