Folded Tele Camera Optics for Large-Aperture Continuous Zoom
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multi-camera systems in mobile devices face challenges in achieving a continuous zoom with large effective focal lengths and low f-numbers while maintaining a compact camera bump size, as the aperture diameter is often limited by the shoulder height, leading to undesired large camera bumps and limited field of view.
Innovation Solution
A folded tele camera design with independently movable lens groups and an optical path folding element allows for continuous variation of effective focal length, featuring a lens configuration where at least one lens element is located on the object side of the optical path folding element, enabling a larger aperture diameter and reduced shoulder height, thus allowing for a more compact camera module.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If a folded tele camera design is used to achieve continuous zoom with large effective focal lengths, then the effective focal length and zoom capability are improved, but the aperture diameter is limited by the shoulder height, resulting in higher f-numbers and reduced light gathering capability
Solution Approach 1:
The patent introduces a lens element positioned at an object side of the optical path folding element, utilizing a different spatial dimension (object side space) to extend the optical path. This dimensional approach allows the light to travel a longer distance before folding, effectively increasing the aperture diameter without proportionally increasing the camera module's physical footprint, thereby improving light gathering capability while maintaining continuous zoom functionality.
Solution Approach 2:
The patent employs independently movable lens groups where at least one lens element can be positioned at an object side of the optical path folding element. This dynamic positioning capability allows the optical system to adaptively optimize the aperture diameter and optical path configuration during zoom operations, enabling the system to maintain larger effective aperture across different focal lengths rather than being constrained by a fixed geometric limitation.
2Illumination intensity
If the aperture diameter is increased to improve light gathering capability and reduce f-number, then the illumination intensity is improved, but the camera bump size increases, reducing the compactness of the mobile device
Solution Approach 1:
By utilizing the object side space relative to the optical path folding element, the patent creates an extended optical path that effectively increases the aperture diameter without requiring a proportional increase in the camera module's horizontal or vertical dimensions. This dimensional approach allows the aperture to be larger than the shoulder height would normally permit, improving light gathering while maintaining a compact camera bump profile.
Solution Approach 2:
The patent divides the lens system into multiple independently movable lens groups, with at least one lens element positioned at an object side of the optical path folding element. This segmentation allows independent optimization of different optical functions: the lens element at the object side contributes to increasing the effective aperture diameter, while other lens groups manage focusing and image formation, thereby achieving large aperture without proportionally increasing the overall camera module size.
3Illumination intensity
If a traditional tele camera design is used to achieve large aperture diameter, then the illumination intensity is improved, but the continuous zoom capability and field of view are limited
Solution Approach 1:
The patent implements independently movable lens groups where at least one lens element can be dynamically positioned at an object side of the optical path folding element. This dynamic configuration enables the system to achieve continuous zoom from wide-angle to telephoto ranges while maintaining a relatively large aperture diameter throughout the zoom range, providing both excellent light gathering capability and versatile field of view adjustment that traditional fixed-aperture tele cameras cannot achieve.
Solution Approach 2:
The patent creates a multi-functional optical system where the same lens configuration serves multiple purposes: the lens element at the object side of the folding element contributes to both increasing the effective aperture diameter for improved illumination and enabling continuous zoom capability across different focal lengths. This universal design eliminates the need for separate optical systems for different functions, achieving both large aperture and continuous zoom in a single integrated camera module.
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
The solution enables a continuous zoom capability with larger effective focal lengths and lower f-numbers while minimizing the camera bump size, allowing for a more compact and versatile mobile device design by reducing the shoulder height and maintaining a larger aperture diameter.
Implementation Method 1
an optical path folding element (OPFE) 204 that folds an optical path (OP) from a first OP 212 to a second OP 208 that forms an optical axis of lens 202
Data Source
AI summary
Folded digital cameras comprising a lens including a plurality of N lens elements marked Li where 1≤i≤N and an optical path folding element (OPFE), wherein a first lens element L1 faces an object side and a last lens element LN faces an image side, wherein at least one of the plurality of lens elements is located at an object side of the OPFE and has an associated first optical axis, wherein at least one other of the plurality of lens elements is located at an image side of the OPFE and has an associated second optical axis, wherein the lens has an effective focal length (EFL) and a f-number (f/#), and an image sensor having a sensor diagonal (SD), wherein the EFL can be varied continuously between a minimal EFLMIN and a maximum EFLMAX by independent movement of lens elements and of the OPFE along the second optical lens axis, and wherein EFLMAX/EFLMIN>1.5.