The invention relates to an apparatus (100) for the performance of optometric measurements, said apparatus (100) comprising: - an opto-adjustable lens (11) whose optical power is adjustable, said lens being governed by a periodic signal configured to produce a optical power wave (200) periodic in time； - means (12) for the adjustment of the mean value of the periodic optical power wave (200)； characterised in that the apparatus (100) further comprises: - an optical projector system (20) to project a plane from the opto-adjustable lens (11) onto a plane external to the apparatus (100)； and in that – the periodic signal has an amplitude such that it produces an amplitude of the periodic optical power wave (200) corresponding to a chromatic difference of focus between a first wavelength and a second wavelength of visible light which crosses the opto-adjustable lens (11). The invention likewise relates to a system for the performance of optometric measurements, and a method for the adjustment of the optical power of an adjustable lens.
