In confocal microscopy, the level of the detected intensity is low, which reduces the contrast of the images. We propose a reflecting optical system to improve the detected intensity. The result of the optimal design is presented and the performance of the resulting reflecting optical system is evaluated. A numerical simulation of the effect of the reflecting optical system on the total system performance is also presented. A standard specimen is imaged to show the benefits of the proposed reflecting optical system. The results in this Note demonstrate a 37% increase of the detected intensity and better contrast of the image. (C) 2004 American Institute of Physics.