Line scan cameras capture one line at a time, building a complete image through motion. They are built for high-speed, continuous inspection of wide surfaces. Their working principle imposes a very specific requirement on illumination: the light must be a uniform, continuous, high-intensity line. That's exactly what a linear fiber optic light guide does. A linear fiber optic light guide takes a bundle of optical fibers — round at the input end to connect to the light source — and rearranges them into a straight line at the output end. Light enters the fiber bundle and exits uniformly from the linear output surface, forming a continuous line of light with no gaps. The fibers are arranged continuously, with no breaks between them. No bright-dark alternation. Four key characteristics: High uniformity. The continuous fiber arrangement means no gaps between light points. No bright-dark zones. With cylindrical focusing lenses and diffusers, uniformity and light density can be further improved. For line scan cameras, uniformity is the top priority — uneven lighting shows up as stripes in the image, and the algorithm can't tell if it's a defect or a lighting artifact. High brightness. Pair it with a high-power cold light source. Low loss, high output. Add a cylindrical focusing lens to concentrate the light further. For high-speed line scan cameras, brightness determines exposure time — and exposure time determines inspection speed. Cold light output. Fiber optics transmit light with virtually no heat at the output end. For heat-sensitive materials — films, paper, precision electronics — this matters. Customizable. Illumination length from 50mm to 1260mm. Fiber material options: plastic (POF), glass (GOF), or quartz. Length and connectors can be customized. For ultra-long linear light, multi-branch input designs allow multiple light sources to feed a single light guide. Linear fiber vs. LED line light: LED line lights are cheaper. But LED chips are discrete points with gaps between them — subtle bright-dark alternation remains. Linear fiber light guides offer continuous output with no gaps — superior uniformity. For high-precision inspection, linear fiber is the more reliable choice. Where it's used: Flat panel display inspection (LCD, OLED), PCB and FPC inspection, semiconductor wafer inspection, web inspection for paper/film/foil, glass and optical component inspection. Line scan camera paired with linear fiber is the standard configuration for these high-speed continuous inspection applications. Selection checklist: Illumination length (must cover the inspection width), fiber material (plastic/glass/quartz), connector type (SMA905 is the standard). For ultra-long lines, use multi-branch input with multiple light sources. Hecho Technology offers linear fiber optic light guides in plastic, glass, and quartz — with illumination lengths from 50mm to 1260mm, and full customization support. For inquiries, contact our technical team.