Capillary array electrophoresis system

A capillary electrophoresis system comprises a planar array of capillaries (1) filled with a migration medium in which samples with fluorophore labels migrate, a source of excitation light (2) exciting the fluorophore labels, a photodetector such as a camera (9) detecting fluorescence from the fluorophore labels, and focusing means (4) placed between the plurality of capillaries (1). The excitation light is irradiated through the plurality of capillaries and light focusing means alternatively placed in the excitation light path. The light focusing means may consist of cylindrical rod lenses (4) with their axes substantially parallel with the capillaries to detect the fluorescence from samples by irradiating a plurality of capillaries substantially at the same time in a batch without mechanical scanning of a plurality of capillaries or without optical scanning of a light beam, providing a highly sensitive detection of samples. The capillaries may be immersed in water (5) where the light (2) passes through.