The principle of thermal radiation blockage in sunroofs refers to the phenomenon where, when direct sunlight strikes the roof glass, near-infrared rays (780nm–2500nm) penetrate the glass and are absorbed by the vehicle's interior materials. This energy is converted into heat, causing the cabin temperature to rise rapidly. Standard glass offers virtually no defense against this specific energy spectrum; real-world tests conducted at noon during the summer show that the surface temperature of the sunroof area can exceed 70°C, thereby indirectly heating both the cabin air and the interior trim. Scientifically speaking, effective heat blockage relies on a composite coating structure characterized by high reflectivity and low light transmittance-rather than simply judging efficacy based on the shade or darkness of the glass.
Although automotive sunroof glass appears transparent, its ultraviolet (UV) light transmittance can exceed 70%; consequently, interior cabin temperatures during the summer can be more than 20°C higher than the ambient temperature outside. This occurs because standard glass offers almost no resistance to near-infrared rays (wavelengths of 780nm–2500nm)-the very type of light primarily responsible for the "greenhouse effect" within the vehicle. A truly effective sun-shading solution does not rely on the depth of color, but rather on whether the material possesses a *reflective* heat-insulation structure-specifically, by embedding a metallic coating or a microporous reflective layer within the base material to deflect heat *before* it makes contact with the interior. The "Starry Sky" edition electric sunshade is designed precisely based on this physical principle: featuring a dual-layer composite structure combined with a vacuum-sputtered aluminum film, it has been empirically proven to block approximately 85% of solar radiant heat while simultaneously preserving the sunroof's original sense of open visibility. It requires no adhesives, necessitates no modifications to the vehicle's original structure, and connects directly to the Tesla CAN bus via a dedicated Y3 interface. The shade offers rapid response times for raising and lowering, operates smoothly and silently, automatically retracts when the vehicle is locked, and deploys instantly upon entry-requiring absolutely no manual intervention.
