The proven Pulsar method tests flicker and contrast sensitivity and has been shown to be both sensitive and specific in the detection of early glaucoma. The stimulus consists of two images forming a ring pattern: the phase and counterphase images that alternate with constant frequency. If flicker-sensitivity is reduced, the phase and counterphase images result in an overlapped image that is no longer visible. By changing the contrast and spatial resolution, full thresholds can be tested.*
* PMID: 19800607