A test device comprising: one or a plurality of supports (20, 20a, 20b, 20c) that supports a plurality of light emitting device (60, 60a, 60b, 60c) subject to a test; a plurality of light waveguides that guides light output from the plurality of light emitting device (60, 60a, 60b, 60c) supported by the one or plurality of supports (20, 20a, 20b, 20c); a plurality of light diffuser plates that respectively diffuses light output from the plurality of light waveguides; a plurality of light receiving devices that respectively receives light diffused by the plurality of diffuser plates; a shield plate, between the plurality of light waveguides and the plurality of light receiving devices, wherein the shield plate has a plurality of openings, each of the plurality of openings arranged to transmit light toward a central area of a light receiving surface of an associated light receiving device (40, 40a, 40b, 40c) and to shield light traveling to an outer periphery of the associated light receiving device (40, 40a, 40b, 40c); wherein each of the plurality of light receiving devices comprises a light receiving element; a package in which the light receiving element is housed; and a light receiving window arranged to cover the light receiving element and being attached to the package by an adhesive provided on the outer periphery of the light receiving window, the light receiving element being sealed inside the package by the package and the light receiving window, the light receiving window forming the light receiving surface on which the light that should be measured by the light receiving device is incident, each of plurality of light emitting devices (60a, 60b, 60c) being arranged to output deep ultraviolet light having a wavelength of 360 nm or shorter; the shield plate is provided to shield light travelling towards the adhesive of each of the plurality of light receiving device. one or a plurality of supports (20, 20a, 20b, 20c) that supports a plurality of light emitting device (60, 60a, 60b, 60c) subject to a test; a plurality of light waveguides that guides light output from the plurality of light emitting device (60, 60a, 60b, 60c) supported by the one or plurality of supports (20, 20a, 20b, 20c); a plurality of light diffuser plates that respectively diffuses light output from the plurality of light waveguides; a plurality of light receiving devices that respectively receives light diffused by the plurality of diffuser plates; a shield plate, between the plurality of light waveguides and the plurality of light receiving devices, wherein the shield plate has a plurality of openings, each of the plurality of openings arranged to transmit light toward a central area of a light receiving surface of an associated light receiving device (40, 40a, 40b, 40c) and to shield light traveling to an outer periphery of the associated light receiving device (40, 40a, 40b, 40c); wherein each of the plurality of light receiving devices comprises a light receiving element; a package in which the light receiving element is housed; and a light receiving window arranged to cover the light receiving element and being attached to the package by an adhesive provided on the outer periphery of the light receiving window, the light receiving element being sealed inside the package by the package and the light receiving window, the light receiving window forming the light receiving surface on which the light that should be measured by the light receiving device is incident, each of plurality of light emitting devices (60a, 60b, 60c) being arranged to output deep ultraviolet light having a wavelength of 360 nm or shorter; the shield plate is provided to shield light travelling towards the adhesive of each of the plurality of light receiving device.