This study extends previous findings on the effect of different levels of short-wavelength light on human alertness. This study explores the alerting ability of long-wavelength light at two levels (40 lx and 160 lx). Eight subjects took part in the 60-minute experiment for each of two nights, during which their objective alertness and subjective alertness were evaluated using electroencephalogram and questionnaire. Results show that both levels increased electroencephalogram beta power, which shows a different pattern compared with the previous findings on short-wavelength light. These results strongly suggest that although short-wavelength light may impact alertness through circadian system, long-wavelength light will have to achieve that through other pathways. The further comparison between current and previous results also suggests that long-wavelength light is just as strong on acute alerting ability, as shown by electroencephalogram measures and self-rating questionnaire, as short-wavelength light.

Short-wavelength light is known to have an effect on human alertness in the night-time. However, there are very few studies that focus on the effect of intensity of light on alertness. This study evaluates the acute alerting ability of short-wavelength light of three different intensities (40 lux, 80 lux and 160 lux). Eight subjects participated in a 60-minute exposure protocol for four evenings, during which electroencephalogram (EEG) as well as subjective sleepiness data were collected. EEG power in the beta range was significantly higher after subjects were exposed to 160 lux light than after they were exposed to 40 lux, 80 lux light or remained in darkness. Also, the alpha theta power was significantly lower under 160 lux light then in darkness. These results show that the effect of intensity on alertness is not linear and further work should be done to investigate the threshold intensity that is required to produce an alerting effect.

An advanced Dyson imaging spectrometer in the near ultraviolet-visible-near infrared region was designed, fabricated, and evaluated. A lens with reflective coating on the back surface is applying to replace the traditional lens-reflecting grating combination. The design concept and fabrication and alignment methods as well as the results of evaluations of the proposed spectrometer are described in detail. The advanced imaging spectrometer achieves high resolution in both spectral and spatial direction and low stray light at a high numerical aperture in the working waveband. The performance of this modified porotype is analyzed and evaluated. Results show the spectrometer is well suited for the remote sensing of the ocean color as well as for various agriculture and vegetation-related applications.

The paper describes the reference torque standard machine with high accuracy and multifunction, developed by our institute, and introduces the structure and working principle of this machine. It has three main functions. The first function is the hydraulic torque wrench calibration function. The second function is torque multiply calibration function. The third function is reference torque standard machine function. We can calibrate the torque multipliers, hydraulic wrenches and transducers by this machine. A comparison experiment has been done between this machine and a deadweight torque standard machine. The consistency between the 30 kNm reference torque machine and the 2000 Nm dead-weight torque standard machine under the claimed uncertainties was verified.

Stimulated by the recent revival of interest in artificial intelligence (AI) and neural networks, I will present a mini tutorial review on the past and present efforts that have been made by researchers toward the goal of happy marriage between optics/photonics (OP) and AI. The review will provide a historical perspective through the eyes of an old researcher in the field of optics who experienced the previous high tide of a neural network boom in the 1980s and who has actively participated in the research of optical neuro computing at the time.