Thermal imaging system adapted to generate edge-enhanced image
View Patent ↗A thermal imaging system adapted to generate an edge-enhanced image is provided to include a first camera module, a second camera module, an array-type near-infrared light source, and a processor. The first camera module receives both of visible light and near-infrared from a target scene, and generates a dual-spectral image based on the visible light and the near-infrared. The second camera module receives far-infrared from the target scene, and generates a far-infrared image based on the far-infrared. The array-type near-infrared light source is disposed to emit near-infrared toward the target scene at different angles simultaneously. The processor generates the edge-enhanced image by overlaying the dual-spectral image on the FIR image using alpha blending, or by extracting dual-spectral edges the dual-spectral image, and overlaying the dual-spectral edges on the FIR image.
1 . A thermal imaging system adapted to generate an edge-enhanced image, comprising:
a first camera module configured to receive both of visible light (VIS) and near-infrared (NIR) from a target scene, and to generate a dual-spectral image that is composed of a VIS image component and an NIR image component based on the visible light and the near-infrared;
a second camera module configured to receive far-infrared from the target scene, and to generate a far-infrared (FIR) image based on the far-infrared;
an array-type NIR light source including a plurality of NIR emitting components disposed to emit near-infrared toward the target scene simultaneously at different angles; and
a processor electrically connected to said first camera module and said second camera module, and configured to generate the edge-enhanced image using one of a first image processing and a second image processing,
wherein, in the first image processing, said processor overlays the dual-spectral image on the FIR image using alpha blending,
wherein, in the second image processing, said processor extracts dual-spectral edges of the target scene from the VIS image component and the NIR image component of the dual-spectral image, and overlays the dual-spectral edges on the FIR image, where the dual-spectral edges contain VIS edge components extracted from the VIS image component, and NIR edge components extracted from the NIR image component,
wherein said first camera module includes a first lens allowing passage of the visible light and the near-infrared, and said second camera module includes a second lens allowing passage of the far-infrared, and
wherein said thermal imaging system further comprises:
a housing accommodating said first camera module, said second camera module, and said processor, and having a lens portion from which said first lens and said second lens are exposed;
an add-on frame detachably mounted to said lens portion of said housing, and having a first opening that is aligned with said first lens, and that is disposed between said first lens and the target scene; and
an optical element mounted in said first opening, and being one of an NIR filter lens, an infrared cut filter, and a macro lens, wherein said NIR filter lens is configured to filter out light with a wavelength falling outside of a spectrum of the visible light and a spectrum of narrowband near-infrared that has a bandwidth of not greater than 40 nm, with a center wavelength of 850 nm. 880 nm, 940 nm or 960 nm.
2 . The thermal imaging system as claimed in claim 1 , wherein said add-on frame further has a second opening that is aligned with said second lens and disposed between said second lens and the target scene.
3 . The thermal imaging system as claimed in claim 2 , further comprising an FIR-blocking element mounted in said second opening, thereby blocking the far-infrared from entering said second camera module.
4 . The thermal imaging system as claimed in claim 1 , wherein said macro lens is a convex lens that has a coating containing germanium and that is configured to have magnifying effect.
5 . The thermal imaging system as claimed in claim 1 , wherein said add-on frame includes one of a magnet configured to magnetically attach to said housing and a tenon configured to interlock with said housing.
6 . The thermal imaging system as claimed in claim 1 , wherein said NIR light source includes a dimmer operable to adjust an intensity of the near-infrared.
7 . The thermal imaging system as claimed in claim 1 , wherein said NIR light source is disposed to emit narrowband near-infrared toward the target scene when said first camera module is capturing an image of the target scene.
8 . The thermal imaging system as claimed in claim 7 , wherein the narrowband near-infrared emitted by said NIR light source has a center wavelength of 850 nm, 880 nm, 940 nm or 960 nm.