Endoscope Optical Path Division for Multi-Depth Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional endoscope apparatuses face challenges in achieving focus at both near and far points without a focus adjustment mechanism, resulting in a shallow depth of field due to the increased number of pixels in image pickup devices, which complicates simultaneous image acquisition and display of focused images at different distances.
Innovation Solution
The endoscope apparatus incorporates a plurality of image pickup devices with different optical path lengths and a contrast comparing member to select the image signal from the device with the highest contrast, utilizing a movable lens and optical path dividing members, such as prisms, to divide the light beam and adjust the optical path lengths for optimal focus.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of pixels of an image pickup device is increased to improve image quality and resolution, then image quality and resolution are improved, but depth of field becomes shallower
Solution Approach 1:
The patent divides the single optical path into multiple optical paths with different optical path lengths, allowing simultaneous imaging at different depths. By segmenting the light beam using optical path dividing members, the system captures images at multiple focal distances concurrently, effectively extending the depth of field without reducing image quality.
Solution Approach 2:
The patent introduces the dimension of optical path length variation by arranging image pickup devices at different positions along the optical axis. This creates multiple imaging planes at different depths, transforming a single-depth imaging system into a multi-depth imaging system, thereby expanding the effective depth of field.
2Adaptability or versatility
If a focus adjustment mechanism is added to achieve focus at both near and far points, then focus flexibility is improved, but device complexity increases
Solution Approach 1:
The patent replaces the mechanical focus adjustment mechanism with an optical path division approach. Instead of moving lenses or image pickup devices mechanically to change focus, the system uses optical path dividing members to create multiple fixed optical paths with different lengths, achieving multi-focus capability without mechanical movement.
Solution Approach 2:
The patent makes a single objective lens serve multiple functions by directing light through different optical paths to multiple image pickup devices. The same lens simultaneously images objects at different depths onto different sensors, eliminating the need for separate focus adjustment mechanisms for each focal distance.
3Adaptability or versatility
If multiple image pickup devices with different optical path lengths are used to capture images at different distances, then depth of field is extended, but device complexity increases
Solution Approach 1:
The patent combines multiple imaging functions into a single integrated optical system. By merging the objective lens with multiple image pickup devices through optical path dividing members, the system achieves multi-depth imaging capability while maintaining a compact and unified structure, reducing overall system complexity despite multiple sensors.
Solution Approach 2:
The patent introduces optical path dividing members as intermediaries between the objective lens and image pickup devices. These intermediaries efficiently split and direct light beams to different sensors, simplifying the optical design compared to using separate optical systems for each image pickup device.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration allows for simultaneous acquisition and display of images focused at near and far points without moving the image pickup optical system, simplifying the apparatus design, improving durability, and achieving a wider depth of field with favorable brightness and image quality.
Implementation Method 1
an optical path dividing member for dividing a light beam entering from an objective lens into a plurality of optical paths and leading the optical paths to a plurality of image pickup devices
Implementation Method 2
an image pickup device which receives an optical image formed by the image pickup objective lens and performs photoelectric conversion to generate an image signal
Implementation Method 3
a driving member for moving a movable lens so that a difference among the contrasts of a plurality of images based on a plurality of image signals outputted from the plurality of image pickup devices, respectively, is largest, wherein a part of the objective lens is configured to be movable in an optical axis direction as the movable lens
Data Source
AI summary
An endoscope apparatus includes an image pickup unit comprising a plurality of image pickup devices and an optical path dividing member for dividing an entering light beam into a plurality of optical paths, wherein respective optical path lengths are different from one another; a contrast comparing member for comparing contrasts of a plurality of images; an image selecting member for selecting and outputting only one image signal from one image pickup device among the plurality of image pickup devices, on a basis of comparison result by the contrast comparing member; and a driving member for moving a movable lens so that a difference among the contrasts of the plurality of images is largest, wherein a part of an objective lens is configured to be movable in an optical axis direction.