Complementary metal–oxide–semiconductor (CMOS) colour image sensors are representative examples of light-detection devices. To achieve extremely high resolutions, the pixel sizes of the CMOS image sensors must be reduced to less than a micron, which in turn significantly limits the number of photons that can be captured by each pixel using silicon (Si)-based technology (i.e., this reduction in pixel size results in a loss of sensitivity). Here, we demonstrate a novel and efficient method of increasing the sensitivity and resolution of the CMOS image sensors by superposing an organic photodiode (OPD) onto a CMOS circuit with Si photodiodes, which consequently doubles the light-input surface area of each pixel. To realise this concept, we developed organic semiconductor materials with absorption properties selective to green light and successfully fabricated highly efficient green-light-sensitive OPDs without colour filters. We found that such a top light-receiving OPD, which is selective to specific green wavelengths, demonstrates great potential when combined with a newly designed Si-based CMOS circuit containing only blue and red colour filters. To demonstrate the effectiveness of this state-of-the-art hybrid colour image sensor, we acquired a real full-colour image using a camera that contained the organic-on-Si hybrid CMOS colour image sensor.

Two novel dipolar donor–acceptor molecules approaching the cyanine limit were used for green-light-selective OPDs.

The coagulation-fragmentation equation describes geodesic motion in an infinite-dimensional space. This space has a symmetric affine connection but no metric in general. Some advantages of the new approach are indicated.

We have investigated a method of fabricating ink-jet printed self-aligned emission zones for top-emission organic light-emitting diodes. To obtain a bright emission, the number of ink-jet printed shots was varied. From the viewpoint of surface roughness of the bottom electrode, AlNd was used. To reduce sputtering damage, a buffer layer with the hole transport ability of MoO3 was also employed. As a result, the maximum luminance obtained was 1,000 cd/m2. By application of this fabrication technique, we have achieved a printed display panel 30×30 mm2 resolution of 300 pixels per inch.