Obviousness

Obviousness Analysis of US Patent 8810803 Under 35 U.S.C. § 103

This analysis identifies combinations of prior art references that would render the independent claims of US patent 8810803 obvious to a person having ordinary skill in the art (PHOSITA) at the time of the invention (priority date: November 12, 2007). The motivation to combine these references stems from addressing known challenges in computer vision systems, specifically improving object detection and tracking by generating more effective light patterns.

General Obviousness Argument

The disclosed lens system in US8810803 aims to overcome a problem in existing interactive display systems, such as those described in U.S. Pat. No. 7,259,747 (referred to as the '747 patent). The '747 patent teaches a system where a light source projects a pattern of invisible light into a three-dimensional space, and a camera and computer system track objects based on this pattern. The problem identified by US8810803 is that if this projected pattern is "too regular... the object may disappear relative to the background when at a particular distance," leading to inaccurate object position determinations. To resolve this, US8810803 proposes generating "random or semi-random dot patterns" using a light source, an optional condenser lens, and a cluster of lenses.

Prior art, such as US Pat. No. 6,254,246 B1 (hereinafter '246 patent), teaches illumination devices that include a light source, a condenser lens, and a microlens array (which constitutes a cluster of lenses) to project patterns or uniformize light. A PHOSITA would have been motivated to combine the teachings of the '747 patent and the '246 patent to improve the object tracking capabilities of the interactive display system. Specifically, a PHOSITA would recognize that the '246 patent's optical system, capable of generating various light patterns, could be integrated with the '747 patent's computer vision system to produce patterns that are less regular or more complex, thereby addressing the "disappearing object" problem identified in US8810803. The use of a condenser lens in such a system is a well-known optical technique for improving light efficiency, a benefit also noted in US8810803.

Obviousness of Independent Claim 1

Claim 1: A system for projecting a pattern of light, the system comprising:

• a light source including a plurality of emitters configured to emit light, the plurality of emitters arranged in a pattern;
• a cluster of lenses located in front of the light source, wherein each lens of the cluster of lenses is configured to receive light from the plurality of emitters and the cluster of lenses is configured to concurrently focus and project light from each of the emitters in a plurality of directions; and
• a condenser lens located between the light source and the cluster of lenses, wherein the condenser lens is configured to concentrate light from each of the plurality of emitters towards a center of the cluster of lenses.

Combination: U.S. Pat. No. 7,259,747 B2 (the '747 patent) in view of U.S. Pat. No. 6,254,246 B1 (the '246 patent).

Analysis:

1. Light source including a plurality of emitters configured to emit light, the plurality of emitters arranged in a pattern: The '747 patent describes an "interactive video display system" where "a light source delivers a pattern of invisible light to a three-dimensional space." US8810803 itself states that its "Lighting source 110 may be akin to the lamp of the '747 patent" and "may also be comparable to the light source of component 10 in FIG. 2 of the '747 patent." This clearly teaches a light source with emitters arranged to project a pattern.
2. A cluster of lenses located in front of the light source, wherein each lens of the cluster of lenses is configured to receive light from the plurality of emitters and the cluster of lenses is configured to concurrently focus and project light from each of the emitters in a plurality of directions: The '246 patent discloses an "illumination device" including a "microlens array" in front of a light source unit. A microlens array functions as a cluster of lenses and is configured to receive light from the light source and project patterns. This inherently involves individual lenses receiving light from emitters and the array collectively focusing and projecting light in various directions. Other references such as US5662401A (integrating lens array) and US6513953B1 (illumination system with lens array) further reinforce the commonality of lens clusters/arrays for light projection.
3. A condenser lens located between the light source and the cluster of lenses, wherein the condenser lens is configured to concentrate light from each of the plurality of emitters towards a center of the cluster of lenses: The '246 patent explicitly describes a "condenser lens" located between the "light source unit" and the "microlens array" in its illumination device. The function of a condenser lens to concentrate light is well-established in optics and is described in the '246 patent's context. US8810803 itself highlights this benefit, stating, "Condenser lens 120 reduces wasted light by redirecting the emitters' light toward the center of the lens cluster 130."

Motivation for Combination:
A PHOSITA, aiming to enhance the performance of the computer vision system taught by the '747 patent—specifically to address the problem of object detection suffering due to overly regular light patterns, as explained in US8810803's background—would be motivated to incorporate a known illumination system like that of the '246 patent. The '246 patent provides the optical components (light source, condenser lens, microlens array) and their functional arrangement for effectively generating and projecting light patterns. By integrating these components into the '747 system, a PHOSITA could produce more varied and discernible light patterns, thereby improving the reliability and accuracy of object tracking. The inclusion of a condenser lens, as taught by the '246 patent, would be an obvious design choice to optimize light utilization efficiency, a common goal in optical systems.

Obviousness of Independent Claim 8

Claim 8: A method comprising:

• emitting, from a plurality of emitters, a plurality of lights arranged in a pattern;
• concentrating, via a condenser lens, the plurality of lights towards a central location of a cluster of lenses;
• receiving the concentrated light at a plurality of points within the cluster of lenses; and
• concurrently focusing, from each lens of the cluster of lenses, the received and concentrated light from each of the plurality of emitters in a plurality of directions.

Combination: U.S. Pat. No. 7,259,747 B2 (the '747 patent) in view of U.S. Pat. No. 6,254,246 B1 (the '246 patent).

Analysis:

1. Emitting, from a plurality of emitters, a plurality of lights arranged in a pattern: Taught by the '747 patent, which describes a "light source" delivering "a pattern of invisible light."
2. Concentrating, via a condenser lens, the plurality of lights towards a central location of a cluster of lenses: This method step is inherent in the operation of the illumination device described in the '246 patent, which positions a "condenser lens" between a "light source unit" and a "microlens array" to direct light.
3. Receiving the concentrated light at a plurality of points within the cluster of lenses: This step naturally follows the concentrating step in the '246 patent's configuration, where the "microlens array" (cluster of lenses) receives the light.
4. Concurrently focusing, from each lens of the cluster of lenses, the received and concentrated light from each of the plurality of emitters in a plurality of directions: This method step is the inherent function of the "microlens array" in the '246 patent, which processes the received light for projection.

Motivation for Combination:
The motivation for combining these method steps is analogous to that for Claim 1. A PHOSITA, aware of the issues with regular patterns in computer vision systems (as highlighted by US8810803) and the solutions offered by optical systems like the '246 patent, would find it obvious to apply the known methods of light pattern generation (emitting, concentrating, receiving, and focusing light using a condenser and lens cluster) within the context of the '747 patent's interactive display system to achieve more effective object tracking.

Obviousness of Independent Claim 15

Claim 15: A system for projecting a pattern of light, the system comprising:

• a light source including a plurality of emitters configured to emit light;
• a cluster of lenses, each lens included in the cluster of lenses being configured to receive the emitted light from each of the plurality of emitters; and
• a condenser lens located between said light source and said cluster of lenses, the condenser lens concentrating light from each of the plurality of emitters towards a center of the cluster of lenses.

Combination: U.S. Pat. No. 7,259,747 B2 (the '747 patent) in view of U.S. Pat. No. 6,254,246 B1 (the '246 patent).

Analysis:

1. A light source including a plurality of emitters configured to emit light: Taught by the '747 patent's "light source" delivering "invisible light."
2. A cluster of lenses, each lens included in the cluster of lenses being configured to receive the emitted light from each of the plurality of emitters: Taught by the '246 patent's "microlens array" positioned to receive light from the "light source unit."
3. A condenser lens located between said light source and said cluster of lenses, the condenser lens concentrating light from each of the plurality of emitters towards a center of the cluster of lenses: Taught by the '246 patent's explicit arrangement of a "condenser lens" between the "light source unit" and the "microlens array."

Motivation for Combination:
The motivation remains the same as for Claim 1. This claim describes a fundamental optical arrangement for pattern projection, where each component (light source, condenser lens, lens cluster) and their relative positions and functions are well-established in the prior art, particularly the '246 patent. A PHOSITA would readily combine these known elements to construct a system for projecting light patterns, especially when seeking to improve the efficacy of computer vision systems as described in the '747 patent.

Conclusion

The combination of U.S. Pat. No. 7,259,747 B2 and U.S. Pat. No. 6,254,246 B1, driven by the desire to address the problem of inconsistent object tracking in computer vision systems due to regular light patterns (as articulated in US8810803 itself), would render independent claims 1, 8, and 15, and many of their dependent claims, obvious to a person having ordinary skill in the art. The '747 patent provides the context of the computer vision application and the need for patterned illumination, while the '246 patent provides the specific optical components and their functional arrangement for generating and projecting such patterns efficiently.