Spherical surface shape error and curvature radius error online detection device and method

The invention discloses a spherical surface shape error and curvature radius error online detection device and method. The device comprises a template, a piece to be tested, a spherical LED light source, an interference fringe acquisition unit, a spherical surface shape error and curvature radius error detection unit and a control unit. The front surface of the spherical LED light source is an irradiation surface and is arranged to face the template, the spherical LED light source is used for providing uniform illumination light of multiple wavelengths, and illumination light sources with at least two selected wavelengths illuminate the template and the piece to be detected gradually in a time-sharing way. The interference fringe acquisition unit is used for collecting and outputting an equal-thickness interference fringe image. The spherical surface shape error and curvature radius error detection unit is used for obtaining the intensity change of the same point on the equal-thicknessinterference fringe imag