Imaging device with extended dynamic range
AssigneePanasonic Corporation
InventorsToshiyuki Sano, Kouichi Hoshino
Life of this patent
Estimating the term…
Abstract
An imaging device comprises: an imaging element (1) capable of reading accumulated charges of different exposure times in a predetermined frame period, the imaging element being divided into groups for long-time exposure and short-time exposure; and a timing pulse generator (2) for adjusting read timings of the imaging element (1). A first read timing at which an accumulated charge of long-time exposure is read from the group for long-time exposure and a second read timing at which an accumulated charge of short-time exposure is read from the group for short-time exposure are adjusted separately from each other. This provides an imaging device that can extend the dynamic range according to the degree of contrast between light and shade of a subject.
Claims12
An imaging device comprising:
- an imaging unit capable of reading accumulated charge signals of different exposure times, in a predetermined frame period, from a plurality of photodiodes which are divided into a long-time exposure photodiode group and a short-time exposure photodiode group;
- a first reader for reading an accumulated charge signal of long-time exposure from said long-time exposure photodiode group at a first read timing after a long-time exposure period in said frame period;
- a second reader for reading an accumulated charge signal of short-time exposure from said short-time exposure photodiode group at a second read timing after a short-time exposure period in said frame period;
- a read timing adjuster for adjusting said first read timing and said second read timing separately from each other;
- a long-time exposure signal generator for generating a long-time exposure signal, using said accumulated charge signal of long-time exposure read from said long-time exposure photodiode group;
- a short-time exposure signal generator for generating a short-time exposure signal, using said accumulated charge signal of short-time exposure read from said short-time exposure photodiode group;
- a synthesizer for synthesizing said long-time exposure signal and said short-time exposure signal to generate an image signal representing the plurality of photodiodes;
- and
- a third reader for reading an accumulated charge signal of long-time exposure from said short-time exposure photodiode group at said first read timing in said frame period,
- wherein said long-time exposure signal generator adds said accumulated charge signal of long-time exposure read from said short-time exposure photodiode group to said accumulated charge signal of long-time exposure read from said long-time exposure photodiode group to generate said long-time exposure signal.
An imaging method wherein an imaging unit capable of reading accumulated charge signals of different exposure times, within a predetermined frame period, from a plurality of photodiodes, which are divided into a long-time exposure photodiode group and a short-time exposure pixel photodiode group, is used, said method comprising:
- adjusting a first read timing after a long-time exposure period in said frame period and a second read timing after a short-time exposure period in said frame period separately from each other;
- reading an accumulated charge signal of long-time exposure from said long-time exposure photodiode group and said short-time exposure photodiode group respectively at said first read timing;
- reading an accumulated charge signal of short-time exposure from said short-time exposure photodiode group at said second read timing;
- generating a long-time exposure signal, by adding said accumulated charge signal of long-time exposure read from said long-time exposure photodiode group and said short-time exposure photodiode group at the first read timing;
- generating a short-time exposure signal, using said accumulated charge signal of short-time exposure read from said short-time exposure photodiode group at the second read timing;
- and
- synthesizing said long-time exposure signal and said short-time exposure signal to generate an image signal representing the plurality of photodiodes.
A non-transitory computer readable medium containing an imaging program for imaging,
- wherein an imaging unit capable of reading accumulated charge signals of different exposure times, within a predetermined frame period from a plurality of photodiodes, which are divided into a long-time exposure photodiode group and a short-time exposure photodiode group, is used, and
- wherein said imaging unit is capable of adjusting a first read timing after a long-time exposure period in said frame period and a second read timing after a short-time exposure period in said frame period separately from each other, and
- said program causes a computer to execute procedures of:
- reading an accumulated charge signal of long-time exposure from said long-time exposure photodiode group and said short-time exposure photodiode group respectively at said first read timing;
- reading an accumulated charge signal of short-time exposure from said short-time exposure photodiode group at said second read timing;
- generating a long-time exposure signal, by adding said accumulated charge signal of long-time exposure read from said long-time exposure photodiode group and said short-time exposure photodiode group at the first read timing;
- generating a short-time exposure signal, using said accumulated charge signal of short-time exposure read from said short-time exposure photodiode group at the second read timing;
- and
- synthesizing said long-time exposure signal and said short-time exposure signal to generate an image signal representing the plurality of photodiodes.
Dependencies are inferred from the claim text.