An optical filter applied to a display apparatus, disposes on a substrate with transparency and has a maximum absorption wavelength .lamda. in a wavelength range of 575.+-.20 nm in connection with a wavelength range from 450 to 650 nm. The optical filter satisfies a relationship, 0.65.ltoreq.T1(.lamda.)/T2(.lamda.).ltoreq.0.90 where T1 (.lamda.) is a transmittance at a central part of the substrate at the maximum absorption wavelength .lamda., and T2 (.lamda.) is a transmittance at a peripheral part of the substrate at the maximum absorption wavelength .lamda.. The optical filter also satisfies a relationship, 0.90.ltoreq.(T1 (.lamda.1)/T2 (.lamda.1))/(T1 (.lamda.)/T2 (.lamda.)).ltoreq.1.05 with respect to transmittances wherein .lamda.1 is each wavelength 450 nm, 530 nm and 630 nm, and .lamda. is the maximum absorption wavelength.

 
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