Uniformly Luminous LED Optical System and Light Fixture

A uniformly luminous LED optical system comprises a reflection cup (1) and a lens (2), wherein the lens (2) is fixed to a light-exiting side of the reflection cup (1);

• the lens (2) is provided with a light-entering surface (21) and a light-exiting surface (22);
• the light-entering surface (21) is located at a side close to the reflection cup (1);
• the light-exiting surface (22) is located at a side away from the reflection cup (1);
• a central incidence hole (11) is provided in the middle of the bottom surface of the reflection cup (1);
• assuming that a cross-section through the central incidence hole (11) divides the reflection cup (1) into two symmetrical parts, the cross-sectional curve l1 of the side wall (12) of the reflection cup (1) is a straight line in the cross-sectional view;
• or
• the cross-sectional curve l1 of the side wall (12) is a reverse arc line;
• two end points of the cross-sectional curve l1 are point A and point B;
• the length of a straight line l2 formed by connecting the point A and the point B is L;
• the straight line l2 is located outside the reflection cup (1);
• the cross-sectional curve l1 intersects the straight line l2 only at the point A and the point B;
• and the maximum vertical distance of the cross-sectional curve l1 from the straight line l2 is H, and 0≤H/L≤0.035.