Standard in perimetry is

Goldmann's perimeter: It consists of a hemispherical dome. Its main advantage over the tangent screen is that the test conditions and the intensity of the target are always the same. It permits greater reproducibility, Goldmann perimeter stimuli I through V. Unless otherwise instructed, the equivalent to Goldmann size III (4 mm2) white target. Reference : AK KHURANA COMPREHENSIVE OPHTHALMOLOGY, Edition4, Page-483,484