Abstract: Provided are an electroluminescent device, a method of manufacturing the same, and a display device including the same, the electroluminescent device including a first electron auxiliary layer, a first light emitting layer, and a first electrode disposed on a first surface of a transparent electrode; and a second electron auxiliary layer, a second light emitting layer, and a second electrode disposed on a second surface of the transparent electrode, wherein the first electron auxiliary layer and the second electron auxiliary layer each include a plurality of zinc oxide nanoparticles, a ratio (t1/t0) of a thickness (t1) of the first electron auxiliary layer to a thickness (t0) of the transparent electrode and a ratio (t2/t0) of a thickness (t2) of the second electron auxiliary layer to the thickness (t0) of the transparent electrode are each in the range of about 0.1 to about 4.0.

Abstract: Measurement of small oscillatory movements of an irregular surface involves the production of a speckle pattern therefrom by coherent light illumination, and the arrangement of a photodetector for direct response to such pattern, variations in photodetector output component at the frequency of the surface movement representing that movement. Another, stationary, illuminated irregular surface can be involved to produce a speckle interference pattern for response of the photodectector thereto and, in the case where the two surfaces are closely adjacent, a single beam can be used to illuminate the first and other surfaces predominantly and by stray light, respectively. This common beam illumination can be used in prior speckle interferometry. The first surface can be an eardrum oscillated by a sound wave, suitably of swept frequency or impulse form, with detection of the photodetector variations respectively being in synchronous manner or by Fourier analysis, respectively.