JPH11289491A - Ccd camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a single CCD to have sensitivity to the wavelength bands of visible light and infrared light by distributively arranging, with a prescribed ratio, transmission parts without infrared ray removal effect and infrared filter parts to cut infrared light for an optical filter which selectively gives a wavelength band of external light to the CCD. SOLUTION: In an optical filter 1 selecting the wavelength band of external light, transmission parts 2 making visible light and infrared light pass through as they are and infrared filter parts 3 cutting infrared light are distributively arranged in a diced form corresponding to the respective picture elements of CCD 4. The whole optical filer 1 is adhered to the surface of a CCD 4. Namely, the infrared filter parts 3 and the transmission parts 2, which correspond to the respective picture element of CCD 4, are distributively arranged in the optical filter 1 in a diced form at a prescribed rate. Thus, sensitivity is given to the wavelength band of infrared light and that of visible light in the single CCD 4 with a small and inexpensive constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CCD (Charge Coupled Device) camera, and more particularly to a CCD camera having sensitivity to both visible light and infrared light.

[0002]

2. Description of the Related Art Although a conventional CCD camera has sensitivity in a wavelength band of infrared light, its characteristic is different from that of visible light. It is configured to approximate an image with normal visible light.

[0003]

However, such a configuration has a problem in that it is necessary to separately provide a CCD for infrared light in order to cope with imaging utilizing infrared light. Was.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a CCD camera in which a single CCD has sensitivity in both visible light and infrared light wavelength bands. Aim.

[0005]

A CCD camera according to the present invention comprises an optical filter for selectively providing a wavelength band of external light to a CCD, a transmission section having no infrared light removing effect and an infrared filter section for cutting infrared light. They are distributed at a predetermined ratio.

According to the present invention, it is possible to make a single CCD sensitive to both visible light and infrared light.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing a configuration of a main part of a CCD camera according to an embodiment of the present invention.
Reference numeral 1 denotes an optical filter for selecting a wavelength band of extraneous light, and a transmission portion 2 that allows visible light and infrared light to pass through as it is, and an infrared filter portion 3 that cuts infrared light. And the optical filter 1
The whole is adhered to the surface of the CCD 4.

The operation will be described. First, the incoming external light 5 of visible light + infrared light passes through the optical filter 1,
The filter transmitted light 6 including the infrared light that has passed through the transmission section 2 is received by the sensor of each pixel of the CCD 4 corresponding thereto, and the infrared cut light 7 that has passed the infrared filter section 3 is received by the sensor of each pixel corresponding thereto. Then, each is converted into an electric signal and taken out as a video signal output 8. In this manner, an image having sensitivity to the wavelength band of infrared light including visible light and an image having sensitivity to the wavelength band of visible light for the single CCD 4 can be obtained in a superimposed manner. The visible light passes through both the transmission part 2 and the infrared filter part 3 of the optical filter 1, whereas the infrared light passes only through the transmission part 2. Therefore, the sensitivity to the wavelength band of the infrared light is visible. The sensitivity is lower than the wavelength band of light.

FIG. 2 is a front view showing another example of the optical filter in one embodiment of the CCD camera of the present invention.
The optical filter 1 includes a transmitting portion 2 that allows visible light and infrared light to pass through as it is, and an infrared filter portion 3 that cuts infrared light. It differs from that shown in FIG. 1 in that it is arranged in a zigzag pattern so as to be larger than the area of the infrared filter section 3. By doing so, the ratio of the sensitivity in the wavelength band of visible light to the sensitivity in the wavelength band of infrared light is higher than that shown in FIG. ,
Since it can be set arbitrarily according to the ratio of the arrangement of the infrared filter section 3, the light receiving characteristics as a CCD camera can be changed. As another example of the optical filter, it is conceivable to replace the transmission section 2 with an infrared ray passing filter. In such a case, a stronger sensitivity can be given to the wavelength band of the infrared light.

As described above, according to this embodiment, the optical filter has a small and inexpensive configuration in which the infrared filter section and the transmission section corresponding to each pixel of the CCD are dispersed and arranged in, for example, a checkered pattern. One CCD can have sensitivity in both the wavelength band of infrared light and the wavelength band of visible light. In the above-described embodiment, a filter arrangement in which the infrared filter unit has a checkered pattern or a staggered pattern has been described as an example, but other filter arrangements can be similarly implemented.

[0012]

As described above, according to the present invention, a single CCD is provided by dispersing a transmission portion and an infrared filter portion at a predetermined ratio in an optical filter for selectively giving a wavelength band of external light to the CCD. An advantageous effect is obtained in that sensitivity can be given to the wavelength band of visible light and infrared light at a desired ratio.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a configuration of a main part in an embodiment of a CCD camera of the present invention.

FIG. 2 is a front view showing another example of the optical filter according to the embodiment of the CCD camera of the present invention;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical filter 2 Transmission part 3 Infrared filter part 4 CCD 5 Extraneous light 6 Filter transmission light 7 Infrared cut light 8 Video signal output

Claims (3)

[Claims] An optical filter for selectively providing a wavelength band of extraneous light to a CCD, a transmission portion having no effect of removing infrared light and an infrared filter portion for cutting off infrared light are dispersed and arranged at a predetermined ratio. To provide sensitivity at a desired ratio to both visible and infrared wavelength bands.
D camera. 2. The CCD camera according to claim 1, wherein a ratio of the transmission portion is larger than a ratio of the infrared filter portion. 3. The CCD camera according to claim 1, wherein the transmission section is an infrared transmission filter.