To meet the requirements for detecting and tracking space debris and to enhance the analytical and predictive capabilities regarding space debris, an optical system has been designed that integrates visible, infrared, and laser paths with a common aperture. The basic specifications are as follows: For the visible spectrum: 400 to 850 nm, field of view of 2° × 2°, focal length of 366.7 mm, and entrance pupil diameter of 100 mm; For the infrared spectrum: 7.5 to 9.5 μm, field of view of 2° × 2°, focal length of 190 mm, and entrance pupil diameter of 95 mm; For the laser spectrum: 1064.4 ± 0.5 nm, field of view of 0.6 mrad, focal length of 370 mm, and entrance pupil diameter of 100 mm. The three optical paths share an off-axis three-mirror structure. By analyzing the design of the free-form surface shape, the first image surface exhibits good imaging quality and coaxial symmetry. The wedge plate is placed backward in front of the first image plane for the laser and infrared channels to correct the aberration caused by the beam splitter, allowing the front groups of the two channels to achieve improved imaging. Consequently, the relay system exhibits coaxial characteristics and can be independently tested and adjusted. Through comprehensive analysis and optimization of aberrations in each optical path, the visible light system achieves an MTF value of 0.44 at the characteristic spatial frequency of 200 lp/mm. The infrared system demonstrates near-diffraction-limited performance with over 80% energy encircled within a 2×2 pixel area, while the laser system achieves >93% energy concentration within a Φ 30 μm region. All channels deliver high-quality imaging performance. This system significantly reduces alignment and assembly complexity and allows modular replacement of relay components as needed, demonstrating broad application potential in space debris detection and orbit determination missions.