Definition of Core Concepts: The Relationship Between Focal Length, Focus Range, and Shooting Distance
In the optical imaging system, focal length determines the lens's ability to converge light and directly affects the imaging angle of view (e.g., the focal length design corresponding to the module's 102° field of view lays the foundation for wide-range observation). Focus range, on the other hand, refers to the object distance interval within which the lens can form a clear image, and it is a key indicator for adapting to the requirements of different shooting distances. For endoscope camera modules, shooting distances are mostly concentrated in the short to ultra-short range. The coordinated design of focal length and focus range directly determines the core performance of "whether target details can be clearly captured" in scenarios such as industrial inspection and medical observation.
Based on the characteristics of the OmniVision OV9734 CMOS sensor, SincereFirst's endoscope camera module sets the focus range at 5-15mm. Combined with the 1/9-inch sensor size and 1.4μmx1.4μm pixel specification, it forms a specialized optimization solution for ultra-short and short-distance shooting. The following sections will analyze the adaptation logic and performance of its focus range in conjunction with the requirements of different shooting distances.
Analysis of Focus Range Adaptability Under Different Shooting Distances
(1) Ultra-Short Distance Shooting (5-8mm): Precise Adaptation for Macro Detail Capture
In scenarios such as industrial micro-part defect detection (e.g., scratches on electronic component pins, micro-abrasion on metal surfaces) or medical microscopic tissue observation (e.g., tiny lesions in the respiratory mucosa), the shooting distance often needs to be controlled within the ultra-short range of 5-8mm. At this point, the 5mm minimum focus distance of the module becomes a core advantage:
Clarity Guarantee: The 5mm minimum focus distance allows the lens to maintain an extremely close distance to the target. Combined with the 1.4μmx1.4μm pixel size, it can maximize the use of the sensor's pixel density, converting tiny details (such as 0.1mm-level scratches) into clear image signals;
Lighting Coordination: At this distance, the 4 LED beads integrated in the lens can provide uniform illumination at close range, avoiding shadow occlusion caused by too short an object distance. Cooperating with the light intake control of the F4.0 aperture, it further improves the imaging contrast of microscopic details;
Operational Feasibility: The 3.5mm lens design with a steel sleeve enables precise control of the distance between the lens and the target during ultra-short-distance shooting, avoiding lens collision damage. At the same time, the manual focus function allows operators to fine-tune clarity to ensure the capture of the most critical detail information.
(2) Short-Distance Shooting (8-12mm): Balanced Adaptation for Short-to-Medium Range Observation
In scenarios such as pipeline inner wall corrosion inspection and observation of assembly gaps of internal equipment components, the shooting distance usually needs to be maintained at 8-12mm to balance "observation range" and "detail clarity":
Coordination Between Field of View and Focus: At this distance, the 102° wide field of view can cover an observation range of approximately Φ15-25mm (calculated based on trigonometric functions). The 8-12mm focus interval ensures that all targets within this range are in a clear imaging state, avoiding both the "local blind spots" caused by the narrow field of view during ultra-short-distance shooting and the detail blurriness during long-distance shooting;
Synchronization of Transmission and Imaging: The USB2.0 speed and 30FPS frame rate can stably output clear images at this distance. When operators adjust the shooting angle through real-time images, the medium-range coverage of the focus range can reduce the operational cost of frequent focusing and improve inspection efficiency;
Environmental Adaptability: The split design allows the lens to flexibly extend into narrow spaces (such as pipelines with a diameter of 20mm) at this distance. The lens structure protected by the steel sleeve can withstand slight collisions, and with LED supplementary lighting, it can maintain clear imaging even in dim internal equipment environments.
(3) Upper Limit of Short-Distance Shooting (12-15mm): Supplementary Adaptation for Wide-Range Observation
In scenarios such as the observation of the overall state of internal cavities of large equipment and the observation of the local macro morphology of organs in medical settings, a shooting distance of 12-15mm can achieve the dual needs of "wider coverage + basic details":
Clear Imaging for Wide Range: The 15mm maximum focus distance allows the lens to remain clear even at a slightly longer distance. Combined with the 102° field of view, it can cover an observation area of approximately Φ30-40mm, facilitating the quick grasp of the overall target state (such as whether there is large-area corrosion in the cavity or abnormal organ morphology);
Balance Between Details and Range: Although the detail accuracy is slightly lower than that of ultra-short-distance shooting, the 1.4μmx1.4μm pixel size can still capture key basic details (such as 1mm-level foreign objects and changes in mucosal color), meeting the inspection logic of "macro judgment first, then local refinement";
Support from Brand Technology: The imaging stability at this distance relies on SincereFirst's AA (Active Alignment) process. By accurately calibrating the relative position between the lens and the sensor, it avoids imaging deviation caused by increased shooting distance and ensures consistent clarity between the edge and center of the image within the 12-15mm range.
Scenario Value of Focus Performance and Brand Guarantee
As can be seen from the above analysis, the 5-15mm focus range design of SincereFirst's module is not a simple interval setting, but a scenario-based logic of "capturing details at ultra-short distances, balancing range and accuracy at short-to-medium distances, and supplementing coverage at the upper limit of short distances", which is highly consistent with the core application needs of endoscopes. This precise parameter design is supported by the brand's 30 years of technical accumulation in the optical equipment industry-from the production environment control of Class 10/100 COB dust-free workshops to the scenario adaptation experience accumulated through cooperation with Fortune Top 500 companies, all of which provide support for the stability of focus performance.
In addition, the 1-year replacement service and 10-year warranty further reduce users' concerns during long-term use: whether it is frequent ultra-short-distance shooting in industrial inspection or the strict requirements for imaging accuracy in medical scenarios, the focus performance of the module can remain stable for a long time. Moreover, the one-stop OEM customization service can also make targeted adjustments to parameters according to the shooting distance requirements of specific scenarios (e.g., the need to shorten the focus range to 3-12mm in the medical field), making the focus performance more in line with users' actual applications.
Conclusion
The 5-15mm focus range of SincereFirst's endoscope camera module, through the coordinated design with focal length, field of view, and pixel size, achieves precise adaptation to three core shooting distances: ultra-short, short-to-medium, and the upper limit of short distances. It not only meets the strict requirements of microscopic detail capture but also takes into account the efficiency requirements of wide-range observation. The brand's advantages in production technology, industry experience, and after-sales guarantee further amplify the scenario value of this focus design, making it a reliable choice in fields such as industrial inspection, medical health, and equipment maintenance.
