Full pixel autofocus (AF) technology: casting images with cores, ushering in a new era of intelligent vision

Overview

Dishan Technology's All-Pixel Auto Focus (AF) Technology in Mobile Image Sensor Chips: Crafting Images with Chips, Pioneering a New Era of Intelligent Vision

In today’s era of rapid advancement in mobile imaging technology, image sensor chips have become the core engine driving the photography capabilities of smartphones. As an innovative enterprise dedicated to the R&D of high-end image sensing technologies, Dishan Technology has, in recent years, leveraged its profound expertise in CMOS image sensors to launch a series of high-performance chip products with independent intellectual property rights. Among these, the groundbreaking application of All-Pixel Auto Focus technology not only demonstrates Dishan Technology’s technical prowess but also delivers an unprecedented focusing experience to smart terminal users. Tests show that this technology can boost the focusing speed of mobile phones to under 0.1 seconds, enabling fast and accurate focusing even in low-light environments, which greatly improves the success rate of photography and the sharpness of photos. Breaking the limitations of traditional focusing methods, this technology redefines the boundaries of smartphone photography clarity and leads the industry into an entirely new era of "what you see is what you get".

Technical Vision: From "Seeing Clearly" to "Focusing Precisely", Reshaping the Essence of Focusing

Traditional mobile image sensors often rely on embedding a small number of Phase Detection Auto Focus (PDAF) pixels within the pixel array during the auto-focus process. These pixels need to sacrifice part of their light-sensing capability to capture phase information, resulting in an inherent trade-off between imaging quality and focusing performance. Especially in low-light, high-speed motion, or complex texture scenarios, issues such as focusing delays, drifts, and even failures frequently occur. Users often encounter the frustration of "blurry shots": blurred moments of motion, "focus hunting" in night photography, and shaky focusing in macro shooting... These pain points have become key bottlenecks restricting the mobile imaging experience.

With a keen insight into these industry challenges, Dishan Technology proposes the technical philosophy of "full-pixel participation, lossless imaging, and intelligent driving", committed to breaking the bottlenecks of traditional focusing technologies. Starting from the underlying architecture, the team has overturned the conventional design paradigm of "separating detection pixels from imaging pixels". Through the independently developed Full-Array Dual Photodiode (FADP) architecture, each pixel unit undertakes the dual tasks of imaging and phase detection simultaneously, truly realizing the concept that "every pixel is a focusing eye". This innovation, enabled by the dual-function design of all pixels, resolves the long-standing dilemma of "choosing between focusing accuracy and imaging quality" in traditional technologies. It not only strikes a perfect balance between the two but also pushes sensor performance to new heights, evolving smartphone photography from "barely seeing" to "focusing precisely". Specifically, by integrating two photodiodes into each pixel, the FADP architecture allows all pixels to participate in focusing, thereby significantly enhancing focusing speed and accuracy while ensuring that imaging quality remains unaffected.

Technical Principles: Full-Pixel Collaboration for Precise Light Direction Sensing, Creating a "Pixel-Level Giant with a Thousand Eyes"

Dishan Technology’s All-Pixel AF technology is based on advanced pixel-level optical design. It integrates two independent photodiodes (Left/Right PD) into each pixel, paired with an optimized On-Chip Lens structure, which focuses light from the left and right sides onto the corresponding photosensitive units respectively. When light enters, the system collects the signal difference between each pair of diodes in real time, quickly calculates the phase shift through on-chip logic circuits, and then determines the current defocus state (front focus or back focus) and degree of the lens. This process is executed in parallel across the entire frame, achieving millisecond-level response and centimeter-level precision auto-focus, as if endowing the sensor with the perception capability of a "giant with a thousand eyes".

Furthermore, Dishan Technology has integrated an Adaptive Focus Engine (AFE) into the sensor chip, which can dynamically adjust focusing strategies based on scene content. For example:

• Portrait Mode: By using AI to recognize eye and facial contours, it prioritizes activating high-precision focusing to ensure sharp and vivid eye expressions, even capturing the subtle flutters of eyelashes.
• Motion Scenarios: It enables a deep learning-based predictive tracking algorithm to anticipate the subject’s movement trajectory in advance, paired with high-frame-rate focusing to clearly freeze moments like a basketball player leaping or a racing car speeding by.
• Macro Photography: By fusing contrast and phase information, it achieves sub-millimeter level precise focusing, rendering even the refracted halos of dewdrops on petals in exquisite detail.

This technology system not only achieves deep collaboration between hardware and algorithms but also reduces system power consumption through on-chip intelligent processing, providing strong support for mobile phone battery life.

Core Technical Advantages: Four-Dimensional Experience Transformation, Redefining Focusing Standards

1.    100% Focus Coverage: Dead-Angle-Free Capture for Unconstrained Composition

Traditional PDAF typically only covers about 50% of the frame area, forcing users to deliberately place the subject within the focusing zone when composing shots. In contrast, Dishan Technology’s All-Pixel AF achieves full-frame, dead-angle-free focusing. Whether it’s a bird at the edge of the frame or a still object in the corner, the focus can be locked instantly, completely liberating creative thinking.

2.    Exceptional Low-Light Performance: A "Focus Beacon" in Dim Environments

With high quantum efficiency design and low-noise readout circuits, the sensor can maintain stable focusing even in extremely dark environments with illumination below 1 lux. Measured data shows that in a pitch-black room, mobile phones equipped with All-Pixel AF technology can focus three times faster than traditional solutions, with a success rate of over 98%, completely eliminating the hassle of "focus hunting in the dark".

3.    Video Focusing: Smooth Transitions Rivaling Cinematic Camera Movements

During 4K/8K video recording, All-Pixel AF supports Continuous Auto Focus (CAF) and object tracking functions. Whether the subject is moving rapidly or the background bokeh is switching, the focus transitions naturally and smoothly without abrupt jumps, providing short-video creators with imaging quality comparable to professional cameras. This feature is particularly notable in live streaming and vlog shooting, allowing creators to focus more on expression rather than technical adjustments.

4.    Low Power Consumption & High Integration: A Performance Powerhouse in Slim Bodies

Dishan Technology adopts an advanced 22nm image sensing process, which improves performance while reducing power consumption by 20%. The chip’s compact layout design (e.g., the DS-IMX8000 series with a 1/1.3-inch large sensor size) balances high pixel density and slimness requirements, saving valuable internal space for flagship smartphones and helping terminal manufacturers create "image flagships that excel in both performance and aesthetics".

Product Implementation and Ecological Collaboration: Empowering the Industry with Technology, Building a New Imaging Ecosystem

Currently, Dishan Technology is actively building an open and win-win ecological system:

In-Depth Joint Tuning with Mobile Phone Manufacturers: It provides customized focusing algorithm optimization services to ensure seamless integration between chips and terminal imaging systems.

Joint Development of New Scenarios with Algorithm Companies: Collaborating with AI vision enterprises, it has launched a "semantic-level focusing" function that can automatically identify specific objects such as pets, food, and cultural relics and prioritize focusing on them.

• Empowering ISP Partners: It opens up the original data interface of All-Pixel AF to help partners develop richer post-processing functions, such as real-time depth adjustment and multi-focus stacking.

This ecological collaboration not only accelerates the commercial implementation of technology but also drives technological iteration across the upstream and downstream of the industrial chain, injecting new momentum into the overall competitiveness of China’s mobile imaging industry.

Future Outlook: Advancing Further into Visual Intelligence, Expanding Technical Boundaries

Looking ahead, Dishan Technology has mapped out a clear evolution roadmap:

1.    AI Perception Integration: Semantic Focusing Unlocks the "Sixth Sense"

It will introduce lightweight neural network models to achieve semantic-level focusing. For example, when shooting pets, it can automatically identify key features like eyes and noses; in sports events, it can accurately track athletes’ body movements; it can even intelligently select the "most story-telling" focus point by analyzing image content, turning the mobile phone into a "user-understanding" shooting companion.

2.    Multi-Modal Fusion Focusing: Building a 3D Visual World

Combining ToF, structured light, and All-Pixel AF, it will develop "multi-modal fusion focusing" technology to build high-precision 3D spatial perception capabilities. This capability will empower emerging applications such as AR navigation, virtual try-on, and spatial scanning, laying the foundation for interactive experiences in the metaverse era.

3.    Moving Toward Higher Frame Rates and Dynamic Range: Breaking Physical Limits

It will develop All-Pixel AF technology supporting high-speed continuous shooting at over 120fps, paired with 12-bit+ high dynamic range imaging, to meet the stringent requirements of professional photography, sports action capture, and extreme environment shooting. For instance, in high-contrast lighting scenarios, it can clearly present both the bright clouds under sunlight and the detailed textures in shadow areas simultaneously.

4.    Automotive and Industrial Applications: Expanding Technical Extensions

It will extend All-Pixel AF technology to fields such as automotive imaging and industrial inspection. For example, it will provide millisecond-level response environmental perception capabilities for autonomous driving systems; it will enable sub-micron-level defect detection for industrial quality inspection equipment, promoting the cross-industry value release of the technology.

Witnessing Every Frame of Reality with the Eye of Technology

In an era where imaging is expression, focusing is not just a technical issue but also the cornerstone of user experience. With the mission of "defining clarity with chips", Dishan Technology has embedded All-Pixel Auto Focus technology into every micron-level structure of its image sensor chips. From the laboratory of technological breakthroughs to the palms of tens of millions of users, from smartphone photography to the broader intelligent vision world, Dishan Technology interprets the power of "China-made chips" through innovation.

When every shutter press precisely freezes a moment, and every frame conveys genuine warmth, Dishan Technology is witnessing every clear and touching moment of the world with its technological eye. In the future, with the continuous evolution of technology, we have every reason to believe that Dishan Technology will continue to lead the wave of mobile imaging technology, turning the vision of "what you see is what you get" into reality and writing a new chapter in how humans record and express the world.