Obviousness

This analysis evaluates the obviousness of US patent 10728436 under 35 U.S.C. § 103, considering prior art references identified within the patent document itself and common general knowledge. The patent, titled "Optical detection apparatus and methods," has a priority date of July 1, 2014.

The core inventive concepts of US10728436, as outlined in its summary and detailed description, include:

• An optical object detection apparatus comprising a lens with a defined depth of field (DoF) and an image sensor, where logic evaluates image contrast to detect objects within the DoF. [cite: "Summary" section]
• A method of detecting an object in an image by producing a high-pass filtered version of the image, determining a deviation parameter of pixels from a reference value, and providing an indication based on this deviation meeting a criterion (e.g., a threshold). [cite: "Summary" section] This high-pass filtering can be based on a convolution operation using a kernel (e.g., Laplacian and Gaussian operators). [cite: "Summary" section]
• A method of navigating a robotic apparatus by obtaining images, analyzing them for contrast, detecting objects based on contrast criteria, and activating an actuator based on the detection, possibly differentiating between targets and obstacles. [cite: "Summary" section]
• Specific optical configurations, such as image sensors disposed at an angle to the lens, multiple discrete image sensors behind a single lens, or multiple image detectors operating at different wavelengths or optical path lengths, to enable distance detection. [cite: "Summary" section, "FIG. 3", "FIG. 4A", "FIG. 4B", "FIG. 4C", "FIG. 4D" sections]

Identified Prior Art References:

The US10728436 patent explicitly incorporates by reference, and thus acknowledges as prior art, the following U.S. patent applications, all filed before the July 1, 2014 priority date of US10728436:

1. P1: U.S. Patent Application Ser. No. 62/007,311 (filed Jun. 3, 2014), entitled “APPARATUS AND METHODS FOR TRACKING USING AERIAL VIDEO”. [cite: "FIG. 12" section]
2. P2: U.S. patent application Ser. No. 14/285,466 (filed May 22, 2014), entitled “APPARATUS AND METHODS FOR ROBOTIC OPERATION USING VIDEO IMAGERY”. [cite: "FIG. 12" section]
3. P3: U.S. patent application Ser. No. 14/285,414 (filed May 22, 2014), entitled “APPARATUS AND METHODS FOR DISTANCE ESTIMATION USING MULTIPLE IMAGE SENSORS”. [cite: "FIG. 12" section]

The patent also references general knowledge regarding existing object detection technologies like "IR-based, ultrasonic, and lidar" systems, acknowledging their use for "target approach/obstacle avoidance by autonomous robotic devices" but noting their limitations. [cite: "Description of Related Art" section]

Obviousness Combinations and Motivation to Combine:

A person having ordinary skill in the art (PHOSITA) in 2014, working in the fields of optical object detection, computer vision, and robotics, would possess knowledge of basic optics, image processing algorithms, and robotic control systems. The identified problems with existing object detection systems (IR, ultrasonic, lidar), as described in US10728436, would provide strong motivation for a PHOSITA to seek improved, more reliable, and cost-effective optical detection methods. [cite: "Description of Related Art" section]

1. Combination of P2 and General Knowledge of Image Processing for Contrast Detection:

• Claims Addressed: The method of detecting an object in an image using high-pass filtering and a deviation parameter [cite: "Summary" section], and the method of navigating a robotic apparatus using contrast parameter analysis for object detection [cite: "Summary" section].
• P2 (US 14/285,466) teaches: Robotic operations that utilize video imagery, indicating that obtaining and analyzing images for robotic control is known. US10728436 itself states that "the trajectory navigation may comprise one or more actions configured to enable landing of the aerial vehicle, e.g., as described in U.S. patent application Ser. No. 14/285,466". [cite: "FIG. 12" section]
• General Knowledge (GK) teaches:
  • It is a fundamental principle in optics and image processing that in-focus images exhibit higher contrast and sharper features compared to out-of-focus images. The patent explicitly states this: "In-focus representations of objects may be characterized by a greater contrast parameter compared to out-of-focus representations." [cite: "Description" section]
  • High-pass filtering, often implemented using convolution with kernels such as Laplacian or Gaussian difference operators, is a standard image processing technique for enhancing edges and other high-frequency content indicative of sharpness and detail. [cite: "FIG. 5A", "FIG. 11A" sections]
  • Quantifying image sharpness or contrast by measuring pixel deviation (e.g., maximum absolute deviation) from a reference value in a high-pass filtered image, and comparing this value to a threshold for detection, are well-established practices in computer vision and autofocus systems. [cite: "FIG. 5A", "FIG. 6A", "FIG. 11A" sections]
• Motivation for Combination: A PHOSITA seeking to implement robust "ROBOTIC OPERATION USING VIDEO IMAGERY" (P2) would be motivated to find reliable methods for object detection from those images. Given the known correlation between image sharpness/contrast and object focus, it would be obvious to apply standard image processing techniques like high-pass filtering and contrast parameter determination (e.g., maximum absolute deviation) to the video imagery. This would provide a quantifiable metric for detecting objects, especially those moving into a fixed depth of field, thus improving the accuracy and effectiveness of robotic operations.

2. Combination of P3 and General Knowledge of Depth of Field in Optics:

• Claims Addressed: The optical object detection apparatus with a lens characterized by a depth of field range and logic to produce an object detection indication based on image contrast breaching a threshold, conveying presence within the DoF range [cite: "Summary" section]. Also, methods and apparatus utilizing multiple image sensors for distance detection, including those arranged at an angle or with varied optical path lengths. [cite: "Summary" section, "FIG. 3", "FIG. 4A", "FIG. 4D" sections]
• P3 (US 14/285,414) teaches: "APPARATUS AND METHODS FOR DISTANCE ESTIMATION USING MULTIPLE IMAGE SENSORS". This directly discloses the concept of using multiple image sensors to estimate distance. US10728436 references P3 in the context of trajectory navigation. [cite: "FIG. 12" section]
• General Knowledge (GK) teaches:
  • The optical principle of Depth of Field (DoF) and its relationship to the Circle of Confusion (CoC), where objects within a specific range appear acceptably sharp in an image. The patent describes DoF and its dependence on f-number as known concepts. [cite: "FIG. 2" section]
  • It is well-understood that by varying the distance of an image sensor from a lens, or by using multiple sensors at different distances, one can achieve focus for objects at different ranges in object space.
• Motivation for Combination: To enhance the "DISTANCE ESTIMATION USING MULTIPLE IMAGE SENSORS" (P3), a PHOSITA would naturally consider how to leverage fundamental optical principles to refine distance measurement. Exploiting the concept of DoF by arranging multiple sensors (e.g., as multiple layers in a 3D sensor, slanted arrays, or using beam splitters to create different optical path lengths for different sensors) to be in focus at different, discrete distance ranges, would be an obvious engineering approach. This configuration allows for the determination of an object's distance by identifying which sensor, or which part of a sensor array, shows the object in sharpest focus (i.e., highest contrast), thereby directly applying the known relationship between focus and distance. The patent itself describes such configurations as enabling "detection of objects disposed within the extent 412 in front of the lens" [cite: "FIG. 3" section] and "detection of objects at multiple locations that differ by distance from the lens plane and the cross axis position" [cite: "FIG. 4A" section].

3. Combination of P1, P2, and General Knowledge of Robotic Control and Object Discrimination:

• Claims Addressed: The method of navigating a robotic apparatus where the detected object is determined to be either a target or an obstacle, and the controller selectively activates the actuator based on this determination for actions like target approach or obstacle avoidance. [cite: "Summary" section]
• P1 (US 62/007,311) teaches: "APPARATUS AND METHODS FOR TRACKING USING AERIAL VIDEO", which inherently involves identifying a "target" (the entity to be tracked) and controlling the aerial vehicle's trajectory (actuator activation) to follow it. [cite: "FIG. 12" section]
• P2 (US 14/285,466) teaches: General "ROBOTIC OPERATION USING VIDEO IMAGERY," including complex actions like vehicle landing. [cite: "FIG. 12" section]
• General Knowledge (GK) teaches: The fundamental requirement for autonomous robotic devices to differentiate between objects they should interact with positively (targets) and objects they should avoid (obstacles). Methods for object discrimination based on visual characteristics (e.g., color, shape, reflectivity) or other sensor inputs (e.g., RFID, acoustic signals) were known. The patent explicitly mentions these discrimination methods. [cite: "FIG. 12" section]
• Motivation for Combination: A PHOSITA developing autonomous robotic systems (P2) that can perform tasks like "TRACKING USING AERIAL VIDEO" (P1) would necessitate the ability to classify detected objects and react appropriately. Integrating object detection capabilities (even those described as existing prior art like IR, ultrasonic, or lidar, or improved optical methods) with a logical layer to distinguish between "targets" and "obstacles" would be an obvious design choice to enable intelligent and safe navigation. The motivation is to enhance the autonomy, safety, and functional capabilities of the robotic system by allowing it to execute specific actions (e.g., approach, avoid, stop, turn) tailored to the nature of the detected object, rather than a generic response.

In conclusion, the various aspects of US patent 10728436, including the use of image contrast derived from high-pass filtering to detect objects within a depth of field, and the application of such detection for robotic navigation and distance estimation using multiple or specialized optical sensors, would have been obvious to a PHOSITA in 2014. This is due to the combination of explicit prior art references (P1, P2, P3) that teach robotic operation, video-based tracking, and multiple-sensor distance estimation, with well-known principles of optics and standard image processing techniques that address the stated needs for improved object detection.