-
15-μm-thick HARP Photoconductive Film
Yuji OHKAWA, Kazunori MIYAKAWA, Tomoki MATSUBARA, Kenji KIKUCHI, Shirou SUZUKI, Misao KUBOTA and Norifumi EGAMI↓summary
- summary
- High-sensitivity HARP photoconductive film, which makes use of the avalanche multiplication
phenomenon, was investigated for the purpose of reporting breaking news at night or producing
nature and science programs. HARP films that are thicker and more sensitive than the previous
8-μm-thick one were studied. Thickening the HARP film causes a problem whereby defects
easily appear during shooting intense spot lights. It was found that controlling the operation
temperature(over 30°C) of the 15-μm-thick HARP film prevents the occurrence of defects.
Moreover, the heat resistance of the film was improved so as to resist temperatures over 30°C.
A reliable 15-μm-thick HARP film whose avalanche multiplication factor is about 200 was
developed.
-
1-inch 256*192 Pixel HARP Image Sensor with Active-matrix HEED
Masakazu NANBA, Yuki HONDA, Yoshiyuki HIRANO, Kazunori MIYAKAWA, Toshihisa WATABE, Saburo OKAZAKI, Yoshiro TAKIGUCHI, Norifumi EGAMI↓summary
- summary
- We developed an active-matrix high-efficiency electron emission device(HEED) that had
scanning driver circuits fabricated with conventional MOS planer technology. A 1-inch 256*192
pixel image sensor, consisting of the active-matrix HEED and a high-gain avalanche rushing
amorphous photoconductor(HARP) target, was fabricated and tested as a step toward the
development of ultrahigh-sensitivity compact image sensors with a large number of pixels. The
experimental results show that the prototype sensor can be used to obtain clear images even
under dark lighting conditions, such as in moonlight, and that the active-matrix HEED is
a promising high-speed image pick-up device.
-
Color separation characteristics of stacked organic photoconductors
Hokuto SEO, Satoshi AIHARA, Toshihisa WATABE, Hiroshi OHTAKE, Misao KUBOTA and Norifumi EGAMI↓summary
- summary
- With the aim of developing compact and high-resolution single-plate color camera, a new type of
image sensor overlaid with three organic photoconductive films each sensitive to only one of the
primary color components was studied. To verify the principle of color imaging in the vertically
stacked structure of organic photoconductive films, we fabricated three organic photodetectors
composed of blue, green and red sensitive organic photoconductive films on individual glass
substrates, and stacked these detectors. Spectral photoresponse characteristics for the stacked
structure revealed that the output signal from each detector had good spectral selectivity, clearly
demonstrating color separation in the vertically stacked structure of organic photoconductive
films.