Ultraviolet ray measuring apparatus for predicting sunburn level and for obtaining SPF values of cosmetics

An ultraviolet ray measuring apparatus comprising:

• first photoelectric converting means having a first light-receiving face and a spectral sensitivity at least in an ultraviolet band of light received from said first light-receiving face, for outputting an electric signal according to an intensity of received light;
• second photoelectric converting means having a second light-receiving face and substantially the same spectral sensitivity as said first photoelectric converting means, for outputting an electric signal according to an intensity of received light;
• first optical filter means, arranged in front of said second light-receiving face of said second photoelectric converting means, for shielding only light of at least a part of said ultraviolet band;
• second optical filter means, arranged in front of said first and second light-receiving faces and having a main transmitting band in said ultraviolet band and a sub-transmitting band on a longer wavelength side than said ultraviolet band, for passing only light having a wavelength of said main transmitting band and sub-transmitting band;
• means for receiving a light shielding substance, said receiving means comprising a light transmitting plate detachably arranged in front of said second optical filter means and having a transmitting band at least in said ultraviolet band, for passing light having a wavelength of said transmitting band;
• arithmetic operation means for computing at least a light intensity in accordance with a difference between said electric signals of said first and second photoelectric converting means;
• and
• display means for displaying a computation result supplied from said arithmetic operation means.