Optic performance is the key characteristic of an Automotive lighting product, it has to achieve the regulation requirements and also be part of styling of the vehicle. As an engineer in Automotive lighting industry, you may know that to verify the optic design, Rapid prototype is needed in the design phase, but do you know what makes the quality of the Automotive lighting prototype? It is optic parts prototype. a good prototype supplier has the capability to make good-quality optic prototypes.
Today, in this article, we will let you get a comprehensive understanding of optic prototypes in Automotive lighting.
What is optic prototype?
Optic prototype is a kind of clear plastic prototype which aim to test optic performance including light distribution and light homogeneity compare with original optic simulations. It is commonly made by CNC machining with transparent acrylic (PMMA) and polycarbonate (PC) materials. It plays a crucial role to verify any protentional issue of optic design.
Optic prototype in Automotive lighting
Light pipe prototype
Light pipes are tubular structures that transmit or distribute light from a light source for illumination purposes or act as optical waveguides. The light pipe tech uses clear plastics as the medium for light transmission. Notably, the light source can be natural, as in sunlight though itâs primarily artificial, typically an LED to a user interface.
Commonly, the diameter of light pipes is varied from 4mm to 8mm with a 1mm to 2mm width optic pillow on the back side of light pipe, these optic pillows are the key features to reflect the light out of light pipe. The material of light pipe in Automotive lighting is polycarbonate for headlamps and acrylic for tail lamps. such as PC2245, PC LC1500, PMMA 8N.
Thick light guide prototype
Thick light guide is a optic part with thick dimensions optic exit surface which could provide a large lit on area with homogenity.
The thickness of light guide is usually from 8mm to 40mm with 1mm to 2mm width optic pillow on the exit surface of light guide. The increased thickness allows for greater control over the propagation and distribution of light.
The material of thick light guide in Automotive lighting is optic grade polycarbonate and acrylic which provide a perfect optic performance. such as PC2245, PC LC1500, PMMA 8N.
Optic thin lens prototype
Optic Thin lenses are made from transparent plastic materials like acrylic or polycarbonate with optic features on A side and B side. The thickness of optic thin lens is usually from 2mm to 3mm depending on the size of the product.
Optic Thick lens prototype
In LED projectors used in car lighting, a thick lens is a optic component in the projector system. It is designed to transfer the light emitted from the LED source to create a desired light output beam pattern.
The thick lens usually have 40mm thickness. it helps create the desired cutoff line or beam shape required for proper automotive lighting, such as low beams or high beams.
How to make a good quality optic prototype
Use high Accuracy CNC machine
To achieve the expected optic performance, optic designer usually designs the optic parts with very small radius to increase the light efficiency of the whole optic system. Normally, 0.1mm radius even less. So, this means that the CNC machine with cutter should achieve the less than 0.1mm radius on the prototype.
KUSLA prototype Use 5-axis precision milling with diamond machining technology to create More complex geometric shapes and precise optical details, the Minimum machining radius R0.05mm and surface tolerance Âą0.02mm.
Use production material plastic sheet
When come to optic prototype of lighting lamps, to verify the original design, production material must be used to achieve the test requirement, then customed acrylic sheet and polycarbonate sheets with production material need to be used for CNC machining. KUSLA Prototype have the capability to make the customed material sheets as below.
| Material | Grade | Thickness |
| PMMA | Clear Evonik PMMA 8N Red Evonik PMMA 8N 33691 Light Red Evonik PMMA 33721 diffusing Evonik PMMA DF23 diffusing Evonik PMMA DF23 Evonik PMMA LD12, LD24, LD48, LD96 | 10mm to 200mm |
| PC | PC2407 PC2405 PC LED2245 PC LC1500 |
Skilled Polishing
Creating a good quality optic prototype requires attention to detail and precise polishing techniques. Hand polishing Acrylic can help present the best clarity and light transmittance.Vapor polishing can be used for the post finishing of machined Polycarbonate parts, which can improve the internal and external surface finish and clarity of the parts.
As a professional prototype manufacturer, KUSLA Prototype have rich experience optic parts polishing skills to achieve the high clarity reqiurement but not break the optic surfaces.
How to check the quality of your optic prototype
Transparency Measurement:
Use a transparency measurement tool such as a spectrophotometer to meaure light transmission rate, then compare with the standard. for clear optic prototype, it usually over 90%.
Radius Measurement:
The smaller radius of the optic prototype, the better optic performance it will have. to measure the radius of optic prototype, Precision measuring instruments, such as calipers or optical profilometers need to be used. for example , the radius of optic light pipe as picture below is reqiured less than 0.1mm.
Visual Inspection:
Carefully examine the surface for any defects, scratches, or blemishes that may affect light transmission or aesthetics under a standard lighting conditions.
Lit-On Visual Check:
Perform a lit-on visual check. lit on the prototype as it would be in its intended application and observe the light distribution. if you found any hotspots or dark areas, compare with the optic simulation then carfully check the optic dimensions of the defect area.
In Summary
Optic prototypes are crucial for Automotive lighting product verification. Light pipes, thick light guides, thin lenses, and thick lenses are clear plastic prototypes used in this process. KUSLA Prototype, with over 10 years of experience and ISO-9001 certification, ensures high-quality and low-cost prototypes. We use advanced CNC machines, custom production material plastic sheets, and skilled polishing for precise optic performance. Transparency and radii are measured with precision tools for validation.
