Patent Application
20130127986
The invention relates to optical systems, and more particularly, to a light weight head mounted imaging system with rapid transitions from far field to near field focus.
Know night vision displays utilize direct axis displays which are both heavy and obstruct the vision of users. The weight of such devices in head mounted systems provides stress on the user's neck. Obstructed vision caused by a monocle or other visor is likewise potentially hazardous to soldiers in the field.
Typical optical systems have focusing at far field is required relatively infrequently, however at near field images rapidly lose focus and must be refocused as the distance between the user and the target item changes. In situations where a user must rapidly view both near field and far field images, the focus at each translation would introduce significant delays and periods of loss of clarity. In field operations, operatives require uninterrupted vision. Thus, current devices are not suitable for covert breeching operations including Close Quarters Battle (CQB) engagements.
At close ranges the depth of field is so small that several focus changes are required to resolve targets at varying close ranges (1-15 m)
What is needed, therefore, are techniques for visual display minimum weight, low profile, and be capable of day/night performance and near/long ranges.
One embodiment of the present invention provides a system for imaging with transition in depth of field, the system comprising: an array of selectably activated sensors comprising first sensors receiving light of a first wavelength and second sensor receiving light of a second wavelength, the first wavelength corresponding to a short effective focal length and the second wavelength corresponding to a long effective focal length; an aperture common to both the first and second sensors configured with chromatic distortion such that a focal plane of light of the first wavelength is different from light of the second wavelength; and a controller, the controller digitally between outputs of the first and second sensors based on the focal length required.
Another embodiment of the present invention provides such a system wherein the first sensors and the second sensor are configured with first and second filters permitting light of the first and second wavelengths respectively to pass through the filter.
A further embodiment of the present invention provides such a system wherein the first and second filters comprise lenslets.
Yet another embodiment of the present invention provides such a system wherein the first and second filters are plasmonic filters.
A yet further embodiment of the present invention provides such a system wherein the light of a first wavelength has a wavelength of between about approximately 520 and 570 nm. 6. The system of claim 1 wherein the light of a second wavelength has a wavelength of between about approximately 630 and 740 nm.
Still another embodiment of the present invention provides such a system wherein the chromatic distortion is axial chromatic distortion.
One embodiment of the present invention provides a system for visual digital display the system comprising: a display disposed proximate to a user's eye and displaying; an array of sensors disposed parallel to the visual axis of the user's eye; the array of sensors collecting data converted into a visual image and displayed on the display, sensors within the array of sensors being selectable by a controller and configured to receive light of a specific wavelength; a common aperture admitting light to the array of sensors, the common aperture being configured with a chromatic distortion; and a controller digitally selecting sensors within the array of a desired depth of field.
Another embodiment of the present invention provides such a system wherein the chromatic distortion is an axial chromatic distortion.
A further embodiment of the present invention provides such a system further comprising graphic overlays on the display.
Still another embodiment of the present invention provides such a system further comprising a chip on thermal imager housing in which the array of sensors is disposed.
A still further embodiment of the present invention provides such a system wherein the display is a holographic display.
Yet another embodiment of the present invention provides such a system wherein the display is retinal painting.
A yet further embodiment of the present invention provides such a system further comprising a head mount whereby the system is affixed to a user's head.
One embodiment of the present invention provides a method for the transition between depth of field, the method comprising: collecting light from a field of view through a double focus/chromatic focus objective lens configured with an chromatic distortion; filtering the light through first and second filters associated with first and second sensors within an array of sensors, such that light entering the first sensor through the first filter focus has a different focus point than light entering the second sensor through the second filter; and digitally selecting between the first and second sensors, thereby selecting the depth of field.
The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not to limit the scope of the inventive subject matter.
One embodiment of the present invention illustrated in
Battery power and system controls are, in one embodiment positioned on the users person, (not shown) armor to reduce head mounted size and weight profile. Additionally, a projection configured according to one embodiment of the present invention has see-through projection technology for situational awareness, depth projection and image overlay
In one embodiment of the present invention illustrated in
In one such embodiment, the eye piece of the imager 14 comprises the largest size and weight component. In order to minimize size and weight, a holographic projection such as that described in U.S. Pat. No. 7,283,307 which is herein incorporated in its entirety for all purposes. In such an embodiment, the sensor array may be disposed parallel to the axis of vision of the user, with the user able to see through the holographic projection while visual overlays of target data, maps, thermal or low level images are overlaid upon the projection. In alternative embodiments, retinal projection or other similar techniques may be employed.
Double Focus/Chromatic Focus Objective Lens 16 are provided configured to induce an intentional axial chromatic distortion as discussed at length with regard to
Image processing electronics 18 may be disposed within the housing, in one embodiment AI-1000 electronics are used for image processing, video in/video out, overlay.
As discussed above, head level integrated mounting, illustrated in various forms in
In one embodiment of the present invention a head mounted night vision display is provided with both different depth of field for near and far field applications. A transition between the far field and near field modes as illustrated in
As illustrated in the flow chart of
The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of this disclosure. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.
