1. A method executed by a measurement device connected to an optical sensor and a display device which is a tablet information terminal independent from the measurement device and configured to communicate with the measurement device via a network communication, wherein a predetermined Web browser on operation in the display device sequentially displays, on the display device, a plurality of different images for adjustment and the measurement device measures, at a predetermined timing, light intensity of the display device displaying each image for adjustment using the optical sensor, the method comprising:a step of transmitting, by the measurement device and via the network communication, to the display device, display control information for causing the Web browser to transmit a content request to the measurement device and to display content each time the content is received;
a step of, in response to the content request by the Web browser, transmitting, by the measurement device, to the display device, first content comprising an image for adjustment and display control information related to a next content to be displayed;
a step of displaying the image for adjustment by the Web browser;
a step of measuring, by the measurement device, the light intensity of the display device displaying the image for adjustment using the optical sensor; and
a changing step of changing, by the measurement device, content to be transmitted, so as to correspond to the display control information in accordance with the timing when the optical sensor performs a measurement,
wherein the display control information includes reload requesting information for automatic reloading by the Web browser, the reload requesting information including information on a reload interval set in accordance with measurement time required for the optical sensor to measure one image for adjustment,
the information on the reload interval is an interval indicated by META tag in an HTML file in the content, and
the Web browser is configured to, upon lapse of the reload interval, automatically and spontaneously according to the specification of the META tag, reload the next content to be displayed, the next content to be displayed being determined by information in the HTML file.