Photons trapped in the form of waveguide (WG) modes associated with the organic–organic interface and in the form of surface plasmon polariton (SPP) modes associated with the metallic electrode–organic interface result in a large energy loss in organic light-emitting devices (OLEDs). Introducing gratings onto the metallic electrode is especially crucial for recovering the power lost to the associated SPP modes. In our research, we demonstrate the efficient outcoupling of SPP modes in TE mode by two-dimensional (2D) grating, which cannot excited in one-dimensional (1D) grating OLED. This causes a 62.5% increase in efficiency from 2D grating OLED than 1D grating OLED. The efficient outcoupling of the WG and SPP modes is verified by the numerical simulation of both the emission spectra and the field distribution.

Combining the requirements of spectrometers for unmanned aerial vehicle platforms, a miniaturized airborne wide-angle push-broom imaging spectrometer with an Offner configuration is designed. The system comprises an objective lens and an Offner-type spectrometer with a spectral range of 400~1000 nm and a spectral resolution of 15 nm. The objective lens and Offner spectrometer are designed in isolation before integration. The front objective lens is an inverted telephoto with a focal length of 13 mm, a relative aperture of 1/4.5, and a field of view of 54°. The frequency of the convex grating in the Offner configuration is 102 LP/mm, and the dispersion width is 2.6 mm. The modulation transfer function of the integrated system is greater than 0.4 at the Nyquist frequency in all spectral bands. To estimate the volume and weight of the system, a preliminary optical–mechanical design scheme is given in this paper. The entire spectrometer has a volume of 130 × 80 × 120 mm and is less than 3 kg, which realizes the miniaturization design of the imaging spectrometer with a wide field of view for unmanned aerial vehicle platforms.

In order to meet the requirement of miniaturization, high image quality and large field of view of monitor lens, based on the characteristics of monocentric lenses, and the development of curved image sensors, we designed a monitor lens optical system and all refraction surfaces and its curved image surface have the same spherical center. The monitoring optical system's FOV is 140°, the focal length is 7.88mm, the F-number is 1.50, and the total length is 14.47 mm. The monitoring optical system is up to 11-megapixel. The final design result shows that the MTF value is closed to the diffraction limit in the central field of view and the 0.7 field of view, and is greater than 0.59 at all fields of view. The RMS radiuses of different fields of view are all less than 1.1 μm . It can be clearly seen that the aberrations of each field of view are well controlled from the quantitative analysis of the transverse ray fan plot. The monitor lens has good performance in quite a large FOV with a miniaturization structure.