An eye refractive power measurement apparatus capable of accurate measurement while preventing noise light from entering a photodetector even a measurement target is moved in an optical-axis direction, has a measurement optical system including an optical axis, a hole mirror having an aperture and a reflective surface, a concave mirror, an optical system projecting measurement light from the target onto a fundus via the aperture and the concave mirror, and an optical system having an image-forming member and the photodetector photo-receiving the light reflected from the fundus via the concave mirror, the reflective surface and the image-forming member, a unit moving the target and the image-forming member or photodetector in the direction to have a positional relationship optically conjugate with the fundus, and a calculation part obtaining eye refractive power based on a travel position or amount of the image-forming member or photodetector and an output from the photodetector.

 
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> Modulation of a video signal with an impairment signal to increase the video signal masked threshold

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