Efficient utilization method for effective area of image sensor

Abstract

The invention discloses an efficient utilization method for effective area of an image sensor. A photosensitive area of an image sensor is divided into two sub-areas, and two optical lenses are used for forming two images in the two photosensitive sub-areas of the image sensor at the same time. If the size of the image is larger than the light sensing sub-area of the corresponding image sensor, the two images formed by the two lenses are partially overlapped on the image sensor; if the size of the image is smaller than that of the light-sensitive sub-region of the corresponding image sensor, the effective pixel of the image sensor cannot be fully utilized. At the moment, before the emergent light rays of the two lenses are mutually overlapped, the polarizing films are arranged on the light paths of the lenses, and the corresponding polarizing films are arranged in front of the two light sensing sub-regions of the image sensor, so that two images can be formed on the image sensor at a time, and the two images are not overlapped; therefore, effective pixels of the image sensor can be fully utilized.

Description

Technical Field

[0001] Optical imaging. Background Technology

[0002] A medical endoscope is a medical device that enters the body through natural cavities or tiny incisions for observation, diagnosis, or treatment. It consists of a lens, light source, and image processing system, and can transmit in-body images in real time. It is widely used in disease examination and minimally invasive surgery in fields such as thoracic surgery, general surgery, neurosurgery, orthopedics, gastroenterology, respiratory medicine, and urology. The image sensors of medical endoscopes are relatively small, especially those of disposable medical endoscopes. The smaller the image sensor, the fewer the effective pixels, making the efficient use of each pixel particularly important. Summary of the Invention

[0003] The light rays emitted from an optical lens typically form a circular image on the optical imaging surface, while the pixels of an image sensor are usually arranged in a rectangle. When the light rays from one optical lens form an image on the photosensitive area of ​​an image sensor, to fully utilize each pixel of the image sensor, the image size is usually larger than the photosensitive area of ​​the image sensor; the portion exceeding this area is not imaged on the image sensor. Dividing the photosensitive area of ​​an image sensor into two sub-regions and using two optical lenses to simultaneously form two images in the two photosensitive sub-regions of the image sensor is problematic. If the image size is larger than the corresponding photosensitive sub-region of the image sensor, the two images formed by the two lenses will partially overlap on the image sensor; if the image size is smaller than the corresponding photosensitive sub-region of the image sensor, the effective pixels of the image sensor will not be fully utilized. Therefore, by placing polarizing films in the optical paths of each lens before the light rays from the two lenses overlap, and placing corresponding polarizing films in front of the two photosensitive sub-regions of the image sensor, it is possible to form two images on the image sensor at the same time without overlap, thus making fuller use of the effective pixels of the image sensor. Attached Figure Description

[0004] Figure 1 This is a schematic diagram showing the placement of the polarizing film. Detailed Implementation

[0005] The photosensitive area of ​​the image sensor (2) is divided into sub-region 1 (3) and sub-region 2 (4). The optical axis extension of lens A (1) passes through the center of sub-region 1 (3), and the optical axis extension of lens B passes through the center of sub-region 2 (4). The image (7) formed by the outgoing light rays of lens A (1) extends beyond sub-region 1 (3), and the image formed by the outgoing light rays of lens B extends beyond sub-region 2 (4). At this time, a 0° polarizing film (6) is placed on the surface of sub-region 1 (3), and a 90° polarizing film (8) is placed on the surface of sub-region 2 (4). At the same time, before the optical path of the outgoing light rays of lens A (1) and the optical path of the outgoing light rays of lens B overlap, a 0° polarizing film (9) is placed on the optical path of lens A (1), and a 90° polarizing film is placed on the optical path of lens B. This makes the outgoing light rays of lens A (1) image only in sub-region 1 (3), and the outgoing light rays of lens B image only in sub-region 2 (4).

Claims

1. A method for efficiently utilizing the effective area of ​​an image sensor, characterized in that: When the outgoing light from two lenses images two different photosensitive areas of the same image sensor, a 0° polarizing film is placed on the surface of one of the photosensitive areas, and a 0° polarizing film is placed at an appropriate position in the optical path of the lens corresponding to that photosensitive area; a 90° polarizing film is placed on the surface of the other photosensitive area, and a 90° polarizing film is placed at an appropriate position in the optical path of the lens corresponding to that photosensitive area. The appropriate position on the optical path is characterized by ensuring that each polarizing film receives light from only a single lens before the optical paths of the outgoing light rays from the two lenses overlap.

Images