Shimadzu Corporation

Tohoku University

Shimadu Corporation

Hideki Tominaga

Yasushi Kondo

Shigetoshi Sugawa

Kenji Takubo

Ryuta Hirose

Rihito Kuroda

Kunihiko Ohkubo

Hideki Mutoh

Shigetoshi Sugaw

A plurality of photodiodes arrayed in a one-dimensional form are divided into a plurality of groups. The structure of an antireflection coating is changed for each group so that all the surfaces of the photodiodes belonging to each group are covered with an antireflection coating having a transmittance characteristic which shows a maximum transmittance within a range of wavelengths of light to be received by those photodiodes. In particular, a SiOcoating layer on the silicon substrate and an AlOcoating layer are common to all the photodiodes, while the structure of the upper layers are modified with respect to the wavelength. Within an ultraviolet wavelength region, the coating structure is more finely changed with respect to the wavelength. By such a design, the transmittance can be improved while making the best efforts to avoid a complex manufacturing process.

Photodiode array for spectrometric measurements and spectrometric measurement system

A burst reading memory section () and continuous reading memory section () are independently provided for each of the two-dimensionally arrayed pixels (). The burst reading memory section () has capacitors (-) capable of holding a plurality of signals. The continuous reading memory section () has only one capacitor. Signal output lines for the two memory sections are separately provided. When a signal produced by photoelectric conversion at the pixel () is outputted on a pixel output line (), the signal can be simultaneously written in the capacitors at both memory sections (), after which the signals can be separately extracted to the outside at different timings. Therefore, a series of images taken at extremely short intervals of time during a short period of time can be obtained at an arbitrary timing without impeding a continuous image-acquiring operation at a low frame rate. Accordingly, both an ultrahigh-speed imaging operation having a limitation on the number of frames and an imaging that is rather slow but has no limitation on the number of frames can be simultaneously performed.

Solid-state image sensor for capturing high-speed phenomena and drive method for the same

A transistor () which acts as a load-current source for a source follower amplifying transistor () for outputting a pixel signal to a pixel output line () is provided in each picture element (), whereby a high bias current is prevented from passing through the high-resistance pixel output line (), so that a variation in an offset voltage among picture elements is suppressed. Inclusion of the high-resistance pixel output line () into the source follower amplification circuit is also avoided, whereby the gain characteristics are prevented from deterioration. Thus, the S/N ratio of the picture element is improved so as to enhance the quality of the images.

Solid state image sensor and method for driving the same

A pixel area with a two-dimensional array of pixels () each including a photodiode and a memory area () on which memory sections for holding signals produced by the pixels for continuously recordable frames are separately provided on a semiconductor substrate. All the pixels simultaneously perform a photocharge storage operation, and the signals produced by the photocharge storage are extracted in parallel through mutually independent pixel output lines (). In a plurality of memory sections connected to one pixel output line, a sample-and-hold transistor of a different memory section is turned on for each exposure cycle so as to sequentially hold signals in a capacitor of each memory section. After the continuous imaging is completed, all the pixel are sequentially read. Unlike CCD cameras, the present sensor does not simultaneously drive all the gate loads. Therefore, the sensor consumes less power yet can be driven at high speeds. The separation between the memory area and pixel area prevents signals from deterioration due to an intrusion of excessive photocharges. As a result, the sensor can perform imaging operations at higher speeds than ever before and yet capture images with higher qualities.

Solid-state image sensor

A floating diffusion () is created substantially at center of the light-receiving surface of an embedded photodiode (), with a gate electrode of a transfer transistor () surrounding the floating diffusion. The concentration (or depth) of impurities in a p-type semiconductor region, n-type semiconductor region or p-well region is changed in an inclined form so that a potential gradient being inclined downwards from the circumference to the center is created when an appropriate bias voltage is applied to the pn junction. The photocharges produced by incident light are rapidly moved along the potential gradient toward the center. Even in the case where the photocharge storage time is short, the photocharges can be efficiently collected since the maximum moving distance from the circumference of the photodiode () to the floating diffusion (). Thus, the photocharges produced by the photodiode () are efficiently utilized, whereby the detection sensitivity is improved.

Solid-state image sensor and method for producing the same

A pixel output line is provided for each of the pixels two-dimensionally arrayed in a pixel area. The pixel output lines are extended to a memory area, and a memory unit is connected to each of those lines. The memory unit includes a writing-side transistor, a reading-side transistor and a plurality of memory sections for holding signals for 104 image frames. A photocharge storage operation is simultaneously performed at all the pixels, and the thereby produced signals are outputted to the pixel output lines. In the memory unit, with the writing-side transistor in the ON state, the sampling transistor of a different memory section is sequentially turned on for each exposure cycle so as to sequentially hold a signal in the capacitor of each memory section. After a burst imaging operation is completed, all the pixel signals are sequentially read. Unlike CCDs, the present device does not simultaneously drive all gate loads, so that it can be driven at high speeds with low power consumption. Thus, the burst imaging can be performed at higher speeds than ever before.

A floating diffusion region is formed at an edge of a light-receiving surface of an embedded photodiode, with a transfer gate electrode located therebetween. A first region, with radially extending portions centered on the FD region, and a second region, located to the outside of the first region, are created in the substantially sector-shaped light-receiving surface. A dopant whose conductivity type is the same as the signal charges to be collected in the first region are introduced, whereby an electric field for moving the signal charges from the radially extending sections towards the center is created due to a three-dimensional field effect. As a result, the charge-transfer time is reduced. Additionally, since a circuit element in the subsequent stage can be placed adjacent to the floating diffusion region, the parasitic capacitance of the floating diffusion region can be reduced and a highly sensitive element can be obtained.

An independent pixel output line () is provided for each of two-dimensionally arranged pixels () within a pixel area (). A plurality of memory sections are connected to each pixel output line (). In a continuous reading mode, photocharge storage is simultaneously performed at all the pixels, and signals are collectively transferred from the pixels () through the pixel output lines () to the memory sections, after which the signals held in the memory sections are sequentially read and outputted. In a burst reading mode, the operations of simultaneously storing photocharges at all the pixels and collectively transferring signals from each pixel () through the pixel output line () to the memory sections are sequentially performed for each of the memory sections to hold signals corresponding to a plurality of frames. When a imaging halt command is given, the holding of new signals is halted, and a plurality of frames of image signals held in the memory sections at that point in time are sequentially read and outputted. Thus, both an ultrahigh-speed imaging operation with a limitation on the number of frames and an imaging mode that is rather slow but has no limitation on the number of frames can be performed.

Solid-state image sensor and drive method for the same

A pixel output line () is independently provided for each of the pixels arranged in a two-dimensionally array within a pixel area so that pixel signals can be sequentially written in a plurality of memory sections () through the pixel output lines (). When a plurality of frames of pixel signals are held in the memory sections (), the pixel signals corresponding to two arbitrarily selected frames are read and respectively stored in sample-and-hold circuits (and), and their difference is obtained. Then, the difference signals corresponding to a predetermined range of the image are integrated, and the integrated value is compared with a threshold. If the integrated value exceeds the threshold, it is presumed that a change in an imaging object has occurred, and a pulse generation circuit () generates a trigger signal. By controlling the discontinuation and other imaging actions according to this trigger signal, it is possible to correctly take high-speed images of the situation before or after the occurrence of an objective phenomenon.

Solid-state image sensor and imaging device

In an image sensor of this invention, each image information detecting unit has one photoelectric converter, eight signal fetch gates for fetching signal charges from the photoelectric converter, and eight store and forward CCD arrays extending parallel to one another and connected to the signal fetch gates, respectively, for storing the signal charges. Only one of the eight signal fetch gates is switched ON in each electronic shuttering cycle synonymous with a photography cycle, to deliver a signal charge to a corresponding one of the store CCD arrays. When signal charges have been stored in all the first cells of the store CCD arrays after eight electronic shuttering cycles, the eight store CCD arrays perform one transfer operation all at once, to forward, in parallel, the eight signal charges to the next cells. This operation is repeated to perform high-speed photography at eight times the transfer speed of the store CCD arrays.

Optical image information detecting apparatus

A two-color radiation thermometer includes an image pickup device having micro photo receiving units arranged two-dimensionally; a light diverging device for diverging incident light coming from a measuring object into two paths and irradiating the light on two different areas on a two-dimensional light receiving surface of the image pickup device; a wavelength limitation device for limiting wavelengths of the light irradiated on the two different areas to first and second wavelengths, respectively; and a temperature calculation device. The calculation device receives image signals corresponding to the first and second wavelengths respectively from the micro photo receiving units located at the two different areas, and calculates the temperature of the measuring object based on the two image signals.

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Uji, Japan

Hideki Tominaga