The aim of this study was to realize spatially uniform illumination of a bacterial suspension using polydimethylsiloxane (PDMS) cells and to demonstrate the potential of a "quorum sensing reactor array". After optimizing the conditions to obtain uniform luminescence, bioluminescent bacterial suspensions with different cell densities were encapsulated in 12 PDMS capsules and placed clockwise. Even without stirring, 11 capsules start/finish illumination in the order of cell density (density ratio ranged from 2(0) to 2(-10)). To realize such an array, spatially uniform bioluminescence was achieved by employing a geometrically symmetric supply of oxygen. A PDMS cell was suitable for this purpose. Suspensions with a depth of less than 2.71 mm showed spatially uniform luminescence without convection. In this study, for the first time, we provide an insight into an inhomogeneous suspension of bioluminescent bacteria. Understanding bacterial behavior at the suspension level, in addition to the genetic and cellular levels, would provide complementary information to comprehensively illustrate bacterial function.