The present invention relates to a
humidity sensor, and more particularly, to a resistance film-type real-time
chromogenic humidity sensor produced with a
polyelectrolyte thin film. The
humidity sensor according to the present invention is a
chromogenic hygrometer in which a
polyelectrolyte nano thin film that absorbs
moisture is formed on a
reflective layer, and the nano thin film varies terms of color and electrical resistance as
moisture is absorbed and the thickness varies. The
hygrometer according to the present invention is a dual-function
hygrometer, the color and resistance of which vary. Provided is the
chromogenic hygrometer in which the sensor made using a PSS-b-PMB thin film varies in color between purple, blue, green, yellow, orange, and red according to humidity at a very high response speed of within one minute.