Autonomous driving often looks like a battle of AI models and computing power. But in the real world, some of the hardest problems are surprisingly human — like being blinded by the sun.
For human drivers, squinting or using a sun visor usually does the trick. For Tesla’s camera-based Full Self-Driving (FSD) system, however, glare has been a long-standing and deeply frustrating challenge. A newly published Tesla patent shows the company is now tackling this issue at the hardware level.
Let’s break down the patent in a simple, question-and-answer format.
What is the sun glare problem in Tesla FSD?
Low-angle sunlight at sunrise and sunset, as well as intense headlight glare at night, can temporarily overwhelm vehicle cameras. When this happens:
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Image sensors lose detail
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FSD perception degrades
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Disengagements become more likely
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Drivers see the dreaded red takeover warning
For a Level 2 driver-assist system, this is mostly an inconvenience.
For a future Robotaxi with no driver — and potentially no steering wheel — it’s a critical failure point.
Why don’t traditional camera glare shields work well enough?
Most vehicle camera housings use simple black plastic glare shields with lightly textured, flat surfaces. While these are designed to absorb light, they still have a major weakness.
When sunlight hits a flat surface at a shallow angle — known as grazing incidence — even matte black materials can reflect a surprising amount of light directly into the camera lens.
In optics, this reflection is measured as Total Hemispherical Reflectance (THR). Tesla’s patent argues that existing designs fail to achieve THR levels low enough for reliable autonomous driving.
What is Tesla’s proposed solution?
According to patent US 2025/0334856-A1, titled “Cone-Textured Glare Shield for Enhanced Camera Vision,” Tesla is replacing flat surfaces with a highly engineered, three-dimensional structure.
In simple terms:
Tesla wants the glare shield to swallow light instead of reflecting it.
What is a micro-cone glare shield?
Tesla’s design uses a dense array of microscopic cone-shaped structures instead of a smooth or lightly textured surface.
Think of the wedge-shaped acoustic foam used in recording studios — but scaled down thousands of times.
Key details from the patent include:
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Cone heights ranging from about 0.65 mm to 2 mm
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Precisely engineered, sharp-tipped cones
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A uniform, non-random arrangement
When light enters this structure, it doesn’t bounce straight back. Instead, it reflects multiple times between the cone walls, losing energy at each interaction until it is effectively absorbed.
The result is a dramatic reduction in reflectance, allowing the camera to see the road — not reflections from its own housing.
Is Tesla using special coatings as well?
Yes. Tesla notes that the micro-cone surface can be combined with ultra-black coatings, similar to Vantablack or carbon-nanotube-based paints.
By pairing physical geometry with advanced light-absorbing materials, the surface approaches a “void-like” appearance that absorbs nearly all incoming light.
What makes this patent truly futuristic?
The most surprising part isn’t the surface texture — it’s that the glare shield can move.
Tesla describes an electromechanical system using stepper motors and actuators that dynamically adjusts the angle of the glare shield in real time.
How does the moving glare shield work?
The system actively tilts the shield based on:
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The sun’s position in the sky
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Vehicle direction and orientation
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Other glare sources, such as headlights
As the car drives, turns, or as lighting conditions change, the shield moves to keep the camera lens in shadow.
You can think of it as an eyelid for the camera.
Why is this important for Robotaxis?
A human driver can say, “I couldn’t see because of the sun.”
A Robotaxi cannot.
For a fully autonomous vehicle, any loss of vision due to glare is unacceptable. This technology directly improves:
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Camera reliability
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Consistency of visual data
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Noise reduction for FSD perception
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Overall system safety
It addresses a physical limitation that software alone cannot solve.
Can something this complex actually be manufactured at scale?
Tesla anticipated that concern as well.
The patent outlines a manufacturing method using sintered steel mold inserts. Although sintered metal appears solid, it contains microscopic pores that allow air to escape during injection molding.
This approach prevents trapped air, preserves sharp cone tips, and enables mass production of extremely fine structures — exactly the kind of manufacturing rethink Tesla is known for.
Why does this patent matter?
This isn’t a flashy concept patent. It targets one of the most persistent real-world edge cases in autonomous driving.
It shows that Tesla isn’t relying solely on neural networks and software training. Instead, the company is redesigning the physical environment around its sensors to give FSD cleaner, more reliable data.
You may never notice this tiny component.
But it could be one of the reasons future Teslas — and Robotaxis — are able to see clearly when it matters most.
