A time-multiplexed stereoscopic display with a wide color gamut is fabricated and introduced in this paper. It comprises a scanning backlight unit (SBLU), a 120Hz liquid crystal display (LCD) panel and a pair of LCD shutter glasses equipped with two switching lens (Manufactured by NVIDIA, Model: 3D VISION 2). We use sectional light guide plates to compress the light angle. We use blue LEDs (Domain wavelength: 450nm) to replace the traditional phosphor white LEDs used in the backlight. The blue LEDs are fixed on the edges of the sectional light guide plates, and the quantum dot-polymer (QDP) film is placed on the surface of sectional plates. The SBLU and auxiliary glasses could work together with the LCD panel. All of these components can be controlled by the vertical synchronization signal transmitted from the graphics card. The color gamut of our prototype is improved. According to ITU-R Recommendation BT.2020 (Rec.2020), the color gamut is widely extended to 77.61%. The display's ability to express color has been improved by using quantum dot (QD) material. The display brightness through the switching lens is about 120 nit. The crosstalk decreases to about 0.9%.