JPH0712645A - Image sensing system by means of radiometer - Google Patents

Abstract

PURPOSE:To contrive the improvement of ground surface resolution without changing the size of a detector by arranging the detector with inclination for a focal point face and lessening a substantially projected area for the focal point face of the detection. CONSTITUTION:Light of an area L2 on a ground surface 2 forms an image on a focal point face 3 through the optical system 4 of a radiometer. Here, a detector 1 is set at an angle of 0 deg.<theta<90 deg.. In a case where theta=0 deg. is indicated, the size of the detector 1 corresponding to the area L2 of the ground surface 2 is d2, in another case where theta>0 deg. is indicated, the size thereof is d1 (>d2). Accordingly, in the other case where the size of the detector 1 is d1 which is constant, in the case of 0 deg.<theta(<90 deg.) the size of the detector 1 can be responded to the area L2 of the ground surface and is equivalent to the case where the ground surface is equivalently observed by the size of d2. This indicates that a practical projected area for the focal point face of the detector 1 becomes small and only its part corresponds to resolution which becomes high.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an imaging system using a radiometer mounted on an artificial satellite, and more particularly to a system for increasing the resolution of the ground surface.

[0002]

2. Description of the Related Art Heretofore, in order to increase the resolution, it has been effective to reduce the size of an image pickup element (herein referred to as a detector) and to increase the focal length of an optical system.

FIGS. 3A and 3B are diagrams showing the size d of the detector 1 corresponding to the area L of the ground surface 2 according to the conventional technique.

As is apparent from FIG. 3, when the focal length f1 of the optical system 4 is not changed, if the size d of the detector 1 is reduced, the area L of the ground surface corresponding thereto is reduced.

Therefore, the smaller the detector, the more
The surface resolution could be increased.

[0006]

In the above-mentioned conventional image pickup method, there is a limit in reducing the size of the detector, and
It is very difficult in manufacturing to make the size extremely small.

Therefore, it is an object of the present invention to provide a method for increasing the resolution without changing the size of the detector.

[0008]

SUMMARY OF THE INVENTION The system of the present invention is characterized by arranging the detectors at an angle to the focal plane,
The effective projected area of the detector with respect to the focal plane is reduced, and the resolution is increased accordingly.

[0009]

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

FIG. 1 is a diagram for explaining one embodiment of the present invention.

The light of one area L2 on the ground surface 2 is focused on the focal plane 3 through the optical system 4 of the radiometer. Here, the detector 1 is installed at an angle of 0 ° <θ <90 ° with respect to the focal plane 3.

When θ = 0 °, the size of the detector corresponding to the area L2 of the ground surface 2 was d2, but θ> 0 °
Then d1 (> d2).

Therefore, when the size of the detector 1 is constant at d1, it is possible to correspond to the area L2 of the ground surface at 0 ° <θ (<90 °), and equivalently, see the ground surface at d2. It is equivalent to

The above corresponds to the fact that the effective projected area of the detector on the focal plane becomes smaller and the resolution becomes higher accordingly.

FIG. 2 is a diagram for explaining another embodiment of the present invention.

In the present embodiment, when it is difficult to arrange the detectors which are angled with respect to the focal plane in the periphery of one focal plane, the optical path splitting element 5 is used to split the optical path on the way.
In this example, a plurality of detectors 1 are arranged around different focal planes.

[0017]

As described above, according to the present invention, the ground resolution is increased without changing the size of the detector by installing the detector at an angle of 0 ° <θ <90 ° with respect to the focal plane. be able to.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an embodiment of the present invention.

FIG. 2 is a diagram for explaining another embodiment of the present invention.

FIG. 3 is a diagram showing a size of a detector corresponding to a ground surface L according to a conventional technique.

[Explanation of symbols]

 1 Detector 2 Ground Surface 3 Focal Plane 4 Optical System 5 Optical Path Splitting Element

Claims (2)

[Claims] 1. An imaging system using a radiometer for measuring incident light from the earth, which is mounted on an artificial satellite, wherein the detector is at an angle θ with the focal plane of the radiometer in a range exceeding 0 degrees and not exceeding 90 degrees. An imaging method characterized by reducing the size of the detector projected on the focal plane by arranging it, and thereby increasing the ground resolution without changing the size of the detector. 2. An imaging method using a radiometer mounted on an artificial satellite for measuring incident light from the earth, splitting the light and placing a detector on the different focal planes of the radiometer and a detector at 0 degree from the focal plane of the radiometer To reduce the size of the detector projected on the focal plane by arranging it at an angle θ in the range of more than 90 degrees and not more than 90 degrees, thereby increasing the surface resolution without changing the size of the detector. Imaging method characterized by.