Akihisa Moriya

Comparison of reflected green light and infrared photoplethysmography

We evaluated the accuracy of pulse rate measurements obtained by reflected green light photoplethysmography (PPG) compared to reflected infrared light photoplethysmography and ECG. The wavelengths of the green and infrared light were 525 and 880 nm, respectively, and experiments were performed at 25°C and at a skin temperature below 15°C. The pulse rate obtained from reflected green light PPG was compared with the ECG RR interval and the pulse rate from reflected infrared PPG. The results indicated a stronger correlation between green PPG and ECG results at both temperatures. These results suggested that reflected green light PPG had an advantage over reflected infrared PPG, especially at temperatures below 15°C.

64.2: Hyperrealistic Display for Automotive Application

We propose a monocular projection head-up display. It uses monocular vision that eliminates the depth cues caused by parallax information and it can control the depth point of the display image. Through examination in a simulator, we confirmed the enhancement of monocular depth perception.

Depth perception control by hiding displayed images based on car vibration for monocular head-up display

We have developed a novel depth perception control method for a monocular head-up display (HUD) in a car. However, it is difficult to achieve an accurate depth perception in the real world because of car vibration. To resolve this problem, we focus on a property that people complement hidden images by previous continuous observed images. We hide the image on the HUD when the car is vibrated. We aim to point at the accurate depth position by using HUD images with having users compliment the hidden image positions based on the continuous images before car vibration. We developed a car which detects big vibration by an acceleration sensor and is equipped with our monocular HUD. Our method pointed at the depth position within a 3.4 [m] error, which was 2 times more accurate than the previous method does.

19.4: Novel Depth Perception Controllable Method of WARP Under Real Space Condition

We developed a compact, 2-liter, monocular head-up display that is WARP-mountable on an automobile. We proposed a novel depth-perception-controllable method and examined the depth perception enhancement characteristics under real space conditions. We confirmed depth perception was controlled as far as 60 meters and true AR was achieved.

Hyperrealistic head-up-display for automotive application

We proposed a novel hyper-realistic head-up display (HUD) concept(WARP) and developed a prototype WARP system. It uses monocular vision that eliminates the depth cues caused by parallax information. Our developed WARP system achieved a free depth control of the HUD image position.

The Development of a System for Sleep Care and Its Applications

This paper describes a new sleep monitoring system for home use. The basic system consists of a wearable physiological sensor and the PC software for analyzing sleep quality from users wrist motion and heart rate variability. Different from a conventional sleep monitoring device used in a hospital, the sensor is so small and easy-to-use that a normal person can use It at home. This means that the system is useful not only for a sleep specialist who wants to check his/her patients daily sleep pattern, but also is useful for self-care. The concepts of the tele-care system and the real-time control of electric appliances for creating better sleep environment are also mentioned.