A new and improved optical measuring method for hematocrit level monitoring devices with a lab chip with a very limited channel height (< 100 m) height and a very small volume (∼10 μL) is designed by merging the LEDs to one body packaged light sources and the scattering-compensating parts. The preliminary optical module composition and analysis was reported in Lab Chip [1]. Our method differs from that of group Sobaszek [2] in the specific method of optical module compositions, basic design, microfabrication methods, and the one-body structure we are using. Finally, we have compared with a clinical laboratory instrument and confirmed that it has worked well with a coefficient of determination (R2) of 0.981 and done the analysis within thirty seconds.