Aiming at problem that intensity uniformity of near infrared LED light source is relatively poor in finger vein image acquisition system

a light source array structure of equilateral triangle is designed. Through using the mathematical model for near infrared LED light intensity and Sparrow’s criterion to optimize distance between two adjacent light source

the optimal distance between the two light sources are confirmed as 6. 26 mm. An uniform illumination area of 10 mm × 20 mm is formed by the new light source array by simulation. The hardware experiment of the light source arrays demonstrate that the light source array of equilateral triangle structure is more prominent than the light sources array of single row in the uniformity and the quality of image.