PowerFlex Control Module

By Innofocus Photonics Technology Pty Ltd

High power stability and precise power control are essential to guarantee the high-quality manufacturing of fibre Bragg grating (FBG). PowerFlex is a fully automated laser power control technology that enables precise control of laser power at a step of 1µW. During the manufacturing process, the exposure time can be controlled to 0.001ms, this enables the exposure time to be consistent. Based on this condition, controlling laser power stability is essential to ensure consistent refractive index differences. Innofocus uses a highly stable femtosecond laser with a real-time pulse power monitoring system. The monitoring system guarantees the stability of laser pulses during long-time continuous operation (>100 hours), and the fluctuation of a single pulse can be controlled within <1%. It enables continuous stable FBG manufacturing and ensures the consistency of the refractive index of each point. It lays a solid foundation for realizing high-performance FBG manufacturing. A schematic of the comparison is shown in Figure 1. Suppose the laser power is not stable. In that case, the distribution of refractive index within the fiber during manufacturing will be uneven, as shown in the case of Figure A, causing an overall lower quality of FBG. Innofocus's high-stability laser can output stable power values for a long time to ensure a uniform refractive index distribution. PowerFlex Module: Precise control of laser power In addition to high power stability, precise power control to adjust the points' size, and refractive index difference Δn are extremely important in optimizing FBG parameters and manufacturing different types of FBGs. To meet this requirement, Innofocus has developed the PowerFlex, a precise power control module. PowerFlex is a fully automated laser power control technology that enables precise control of laser power at a step of 1µW. Flexibility in various laser power control Our intelligent femtosecond laser power control technology can also meet the needs of introducing different refractive index distributions. As shown in Figure 2, the points in an FBG manufactured by a high laser power are larger in size with a higher refractive index change (Figure A), whereas points manufactured at a low power are smaller in size (Figure B). By changing the system's parameters, various flexible needs can be met. The fully automated power system effectively avoids the variation in quality caused by laser power fluctuation. It allows for long-time, large-scale, repeated FBG manufacturing, resulting in high-quality mass production of FBG.