A 90-degree prism splitting method

Abstract

A 90-degree beam splitting method using prisms. Current rigid optical 3D systems employ dual-lens (rigid optical endoscopes contain two independent optical paths to propagate two beams of light) or dual-CMOS (cameras contain two image sensors, each receiving one beam of light to form an image) solutions, which are complex in structure, high in cost, and limited in size. This method uses two sets of specific prisms at the exit pupil position of rigid optical endoscopes (such as thoracoscopes, laparoscopes, neuroendoscopes, etc.) to split the emitted light into two sub-beams. Due to the characteristics of the exit pupil position, each of these two beams can form a complete image, and these two images include parallax, meaning single-beam 3D imaging is possible. This technical solution has a simple structure, low cost, and can be made smaller.

Description

Technical Field

[0001] Optical imaging. Background Technology

[0002] A rigid optical endoscope system consists of a rigid optical endoscope and an endoscopic camera system. The rigid optical endoscope has an objective lens and an eyepiece, while the endoscopic camera system consists of a main unit, a camera, and an optical adapter. The rigid optical endoscope and the camera are connected via the optical adapter. Light enters from the objective lens of the rigid optical endoscope and exits from the eyepiece. The light emitted from the eyepiece is then transmitted to the optical adapter, and the light emitted from the optical adapter forms an image on the image sensor. Summary of the Invention

[0003] Current rigid optical 3D systems employ dual-lens (rigid optical endoscopes contain two independent optical paths to propagate two beams of light) and dual-CMOS (cameras contain two image sensors, each receiving one beam of light to form an image) solutions, resulting in complex structures, high costs, and size limitations. A new approach involves using two sets of specific prisms at the exit pupil of rigid optical endoscopes (such as thoracoscopes, laparoscopes, and neuroendoscopes) to split the emitted light into two sub-beams. Due to the characteristics of the exit pupil, each of these two beams can form a complete image, and these two images include parallax, enabling single-beam 3D imaging. This technical solution is simple in structure, low in cost, and can be made smaller. Attached Figure Description

[0004] Figure 1 It is a complete optical path diagram. Detailed Implementation

[0005] At the exit pupil position P(2) in the direction of the outgoing light ray (1) of the optical lens S (such as: rigid optical endoscopes for medical use such as thoracoscopes, laparoscopes, neuroendoscopy, or other optical lenses), the light ray (1) is divided into sub-ray A(5) and sub-ray B(6) by prism A(3) and prism B(4).

[0006] The characteristic of the exit pupil position P(2) is that, ideally, any point on the optical path cross-section at this position will receive the light reflected from various positions on the surface of the subject and entering the optical lens (without a light-blocking aperture). That is, any point on the optical path cross-section at position P(2) can form a complete image. Different points on the optical path cross-section at position P(2) contain views of the subject from different perspectives.

[0007] Prism A (3) and prism B (4) are completely identical and used in the same way. Prism A (3) is a right-angle prism. Prism A (3) consists of 5 faces, two of which are parallel to each other and are non-working faces. The other three faces, which are perpendicular to the non-working faces, are the working faces. The working faces have one inclined plane (the face facing the right angle) and two right-angled faces (the two faces forming the right angle). The right-angled faces are the refractive surfaces, and the inclined planes are the reflective surfaces. One right-angled face (7) of prism A (3) and one right-angled face (8) of prism B (4) are perpendicular to the optical axis (9) of the optical lens S. The intersection of the light path section of ray (1) at the exit pupil position P (2) with the optical axis (9) is Q (10). The plane containing the right-angled face (7) of prism A (3) and the plane containing the right-angled face (8) of prism B (4) pass through point Q (10).

[0008] After this, prism A (3) can only move in a direction perpendicular to the optical axis (9), and prism B (4) can only move in a direction perpendicular to the optical axis (9). Sub-ray A (5) is refracted by the right-angled surface (7) of prism A (3) and enters the prism to continue propagating. It reaches the inclined surface (11) of prism A (3), is reflected by the inclined surface (11), and reaches the right-angled surface (12) of prism A (3). It is refracted by the right-angled surface (12) and then exits. The angle between the right-angled surface (7) and the right-angled surface (12) is 90 degrees, so after the sub-ray (5) exits from prism (3), the direction of propagation of the ray changes by 90 degrees. Sub-ray B(6) is refracted by the right-angled facet (8) of prism B(4) and continues to propagate inside the prism, reaching the inclined facet (13) of prism B(4). After being reflected by the inclined facet (13), it reaches the right-angled facet (14) of prism B(4) and exits after being refracted by the right-angled facet (14). The angle between the right-angled facet (8) and the right-angled facet (14) is 90 degrees, so after the sub-ray B(6) exits from prism (4), the direction of propagation of the ray changes by 90 degrees.

[0009] Because the image sensor (15) is usually perpendicular to the optical axis (9) and located in the direction of propagation of the light ray (1), a right-angled prism C (16) can be used to change the direction of propagation of the light ray emitted from prism A (3) by 90 degrees; and a right-angled prism D (17) can be used to change the direction of propagation of the light ray emitted from prism B (4) by 90 degrees. In this way, sub-ray A (5) and sub-ray B (6) with the same direction of propagation as the light ray (1) are obtained.

[0010] Next, simply adjust the imaging quality and imaging size of sub-ray A (5) and sub-ray B (6) respectively, and sub-ray A (5) and sub-ray B (6) can each form an image on the image sensor (15). These two images have parallax and can form a 3D image pair (18).

Claims

1. A 90-degree prism spectral dispersion method, characterized in that: At the exit pupil position in the direction of the emitted light from an optical lens, two prisms are used to split the light into two paths. The exit pupil position is characterized in that: any point on the optical path cross section at this position will, under ideal conditions, receive the light reflected from various positions on the surface of the object being photographed and entering the optical lens (without a light-blocking aperture); The prism is characterized in that: it is a right-angle prism composed of 5 faces, of which two parallel faces are non-working faces, and the other three faces are working faces. Each working face has an inclined plane (the face facing the right angle) and two right-angled faces (the two faces forming the right angle). Among the three working faces of the prism, the inclined plane is the reflecting face, and the right-angled faces are the refracting faces. One of the right-angled faces of the prism is on the same plane as the optical path cross-section of the outgoing light ray from the aforementioned optical lens at the exit pupil position. After completing the above steps, the prism can only move in a direction perpendicular to the optical axis of the optical lens. The light ray is refracted from one of the right-angled faces into the prism and propagates inside the prism, then reaches the inclined plane, is reflected by the inclined plane, reaches the second right-angled face, is refracted by the second right-angled face, and then exits the prism. The two prisms are characterized in that, in order to make the structure more compact, the parts of the prisms that do not receive light can be cut off.

Images