Television – Camera – system and detail – With single image scanning device supplying plural color...
Reexamination Certificate
1997-05-29
2001-10-16
Ho, Tuan (Department: 2612)
Television
Camera, system and detail
With single image scanning device supplying plural color...
C348S229100
Reexamination Certificate
active
06304293
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a solid-state image pick-up system, and more particularly to a solid-state image pick-up system based upon a field-sequence technique.
2. Related Art Statement
So far, various types of solid-state image pick-up systems have been proposed, which are equipped with a rotary filter conducting a color separation with a solid-state image pick-up device, and as one instance there has been known a field-sequence type solid-state image pick-up system. This field-sequence type solid-state image pick-up system separates light incident on a solid-state image pick-up device through the use of a rotary filter into R, G, and B in time sequence, with the solid-state image pick-up device outputting R, G, and B time series signals during one revolution of the rotary filter. Further, the R, G, and B signals in the time sequence are put in given memories, respectively, and the output signals are made to simultaneously occur in a manner that the reading timings thereof from the memories are set to be coincident with each other, and then delivered to a monitor or other output after undergoing a given process.
One example of arrangements of the prior field-sequence type solid-state image pick-up system will be described hereinbelow with reference to FIG.
22
.
In the illustration, the solid-state image pick-up system is provided with a camera lens
2
accepting an incident light beam
1
such as a subject light beam on the front side of camera body
3
, while being equipped with a R, G, and B rotary filter
4
located in the rear of the camera lens. In addition, a solid-state image pick-up device
5
is located at the back of the rotary filter
4
, with the subject light beam separated through the rotary filter
4
into R, G, and B components which are incident on the solid-state image pick-up device
5
.
The output signal of the solid-state image pick-up device
5
is amplified through a preamplifier
6
and then outputted through an A/D converter
12
, a signal processing circuit
13
including a simultaneously generating circuit
13
, a D/A converter
14
and an output terminal
15
to external equipment.
On the other hand, the camera body
3
has a synchronizing signal generating circuit
9
, so that the rotary filter
4
and the solid-state image pick-up device
5
are driven by an electric motor
8
and a drive circuit
10
which operate in accordance with a synchronizing signal produced in the synchronizing signal generating circuit
9
. Further, the rotation of the rotary filter
4
is detectable by means of a photointerrupter
7
disposed in the vicinity of the rotary filter
4
, with the detection signal being inputted into the synchronizing signal generating circuit
9
to execute the control of rotation of the rotary filter
4
. The drive circuit
10
is composed of a pulse drive circuit and a bias circuit for the drive of the solid-state image pick-up device
5
.
In the field-sequence type solid-state image pick-up system with the above-mentioned arrangement, when the solid-state image pick-up device
5
outputs the R, G, and B time series signals during one revolution of the rotary filter
4
, for reading out the signals from the solid-state image pick-up device
5
, there are known: a first method in which group of one fields (for example, odd number fields) of the R, G, and B signals are read out therefrom at the first cycle of the rotary filter
4
whereas another group of fields (for example, even number fields) are read out therefrom at the second cycle thereof; and a second method in which both the fields of the R, G, and B signals are read out therefrom for a time period corresponding to one revolution of the rotary filter
4
.
Assuming that the accumulation time for one color of R, G, and B takes {fraction (1/60)} second, since according to the first method the reception of one picture is possible with 3 fields, it is possible to output 20 pictures in a period of 1 second. On the other hand, according to the second method, the reception of one picture is practicable with 6 fields so that the output of only 10 pictures is made in a period of 1 second. This signifies that both the first and second methods take 0.1 second for the reception of a picture of one frame.
Consequently, the first method is advantageous in reducing the so-called color shift which can occur because at the pick-up of a dynamic picture the subject moves during the time period of one revolution of the rotary filter
4
so that the R, G, and B differ in position.
For sensitizing in such a case as to photograph a subject with a low illuminance, there has been known a way of lengthening the accumulation time per one color as compared with the case of a subject with a common brightness. However, assuming that the accumulation time for one color is 1 second, the above-mentioned first method requires 6 seconds for the reception of one-frame picture, thus deteriorating the operating performance.
OBJECTS AND SUMMARY OF THE INVENTION
Accordingly, it is a first object of the present invention to provide a solid-state image pick-up system which is capable of minimizing the time needed for the reception of a picture even in the case of the lengthened accumulation time.
A second object of this invention is to provide a solid-state image pick-up system which is capable of shortening the picture reception time even in a high-sensitivity mode.
A third object of this invention is to provide a solid-state image pick-up system which is capable of improving an S/N ratio in a standard mode.
A fourth object of this invention is to provide a solid-state image pick-up system in which the switching to a standard mode shortening an accumulation time in a solid-state image pick-up device automatically takes place in the case of switching from a still or static picture to a dynamic picture in a high-sensitivity mode, thus lessening the color shift.
A fifth object of this invention is to provide a solid-state image pick-up system which is capable of distinguishing between a dynamic picture and a still picture through a microscope without depending upon a subject for sure switching to a standard mode.
A sixth object of this invention is to provide a solid-state image pick-up system which is capable of improving an S/N ratio in accordance with an input signal level.
A seventh object of this invention is to provide a solid-state image pick-up system which is designed to automatically switch from a high-sensitivity mode to a standard mode, thus enhancing its controllability.
An eighth object of this invention is to provide a solid-state image pick-up system in which, in the case of focusing under a microscope, a decision is made that it is under the focusing even if difficulty is encountered to size up the focused condition and the switching to a standard mode is made on that decision.
A ninth object of this invention is to provide a solid-state image pick-up system having simplified circuitry.
A tenth object of this invention is to provide a solid-state image pick-up system which is capable of resolving the occurrence of a difference between an odd number field and an even number field.
Briefly, a solid-state image pick-up system according to the present invention comprises: an image pick-up lens for forming an image corresponding to an incident light from a subject on an image pick-up plane; color separation means for separating the incident light into a plurality of color components at a given cycle or period; a solid-state image pick-up device for receiving the subject light separated in the color separation means to convert it into a given subject image signal; image pick-up mode selection means for selecting a standard mode for picking up a dynamic picture and a high-sensitivity mode for picking up a still picture; and control means for controlling the cycle of the color separation means in accordance with the output of the image pick-up mode selection means.
These as well as other objects and advantages of the present invention will become further
Itoh Hiroshi
Kubota Akihiro
Noguchi Toshiyuki
Sugimoto Yukihiro
Ho Tuan
Olympus Optical Co,. Ltd.
Volpe and Koenig P.C.
LandOfFree
Solid-state image pick-up system having a color separating... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Solid-state image pick-up system having a color separating..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Solid-state image pick-up system having a color separating... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2569418