Patent Application
20120250145
1. Field of the Invention
The invention relates generally to optical devices, and more particularly, to optical magnification devices for use in the presence of a source of electromagnetic radiation.
2. Background Information
Lasers have found utility in a number of applications, including, for example, communications, energy production, electronics, cosmetology, dermatology, medicine, and dentistry. Light (or electromagnetic radiation) emitted from a laser, predominantly by stimulated emission, is extremely intense, coherent, monochromatic, and highly collimated. When a laser is used, for example, during a medical or dental procedure, the surgeon or dentist must wear an eye protection device, for example, laser safety glasses, to avoid damage to the eye, as the beam produced by the laser can cause significant damage to the eye.
In addition to lasers, magnification devices may be also used, for example, by surgeons and dentists during medical or dental procedures, for magnifying a work area requiring precision. The magnification devices used may include telescopes, microscopes, endoscopes, and eye-loupes.
Exposure to laser beams in the visible (400 nm to 700 nm) and near-infrared (700 nm to 1400 nm) regions of the spectrum (retinal hazard region) may damage the retina, particularly when viewed through magnifying optical devices, as the energy concentration of a laser beam may increase up to one million times. Although infrared lasers (1.400 μm to 1 mm) and ultraviolet lasers 0.180 μm to 0.400 μm) do not present a retinal hazard, damage to the eye can still occur.
Currently available laser safety glasses or goggles filter out the wavelength or wavelengths emitted by the laser, with the goal of providing maximum visible light transmission (VLT). To filter out the wavelength, chemical additives or dyes may be added to a filter (in the form of a lens), which may be formed of polycarbonate, glass, or other suitable material, to match and consequently absorb the wavelength and power of the source of laser radiation. In addition to absorptive, reflective filters may also be used.
Depending upon the laser and the application, the attenuation or optical density, Dλ, (OD) of the filter lens at a specific wavelength should be specified. Since lasers may radiate at more than one wavelength, eyewear designed to have an adequate OD of a particular wavelength may have an inadequate OD at another wavelength for light emitted by the same laser. Most eye protection glasses or goggles use selective wavelength attenuation to protect eyes from harmful laser radiation while permitting the eyes to see something of interest, by filtering radiation inside and outside the visible range, yet many of the currently-available devices are cumbersome or uncomfortable when used in conjunction with an optical magnifying device.
Accordingly, there remains a need for optical magnification devices suitable for use in the presence of a radiation-emitting source to protect the eyes of a user.
Briefly described, according to an aspect of the invention, a magnification device includes a housing including a distal open end and a proximal open end; an optical system including one or more objective lenses mounted in the housing adjacent the distal open end, and one or more eye lenses mounted in the housing adjacent the proximal open end; and a filtering system suitable for attenuating selected wavelengths from the transmission of electromagnetic radiation including a first filter lens mounted to the distal open end of the housing adjacent the one or more objective lenses, and a second filter lens mounted to the proximal open end adjacent the one or more eye lenses, the first filter lens closing the distal open end of said housing.
According to another aspect of the invention, a vision enhancing assembly includes a carrier device; one or more magnification devices coupled to the carrier device, each of the magnification devices including: a housing including a distal open end and a proximal open end; an optical system including one or more objective lenses mounted in the housing adjacent the distal open end, and one or more eye lenses mounted in the housing adjacent the proximal open end; and a filtering system suitable for attenuating selected wavelengths from the transmission of electromagnetic radiation including an external filter lens mounted to the distal open end of the housing, and an internal filter lens mounted to the proximal open end, the exterior filter lens closing the distal open end of the housing.
As used herein, the terms “comprises”, “comprising”, “includes”, “including”, “has”, “having”, or any other variation thereof, are intended to cover non-exclusive inclusions. For example, a process, method, article or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. In addition, unless expressly stated to the contrary, the term “of” refers to an inclusive “or” and not to an exclusive “or”. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present); A is false (or not present) and B is true (or present); and both A and B are true (or present).
The terms “a” or “an” as used herein are to describe elements and components of the invention. This is done for convenience to the reader and to provide a general sense of the invention. The use of these terms in the description herein should be read and understood to include one or at least one. In addition, the singular also includes the plural unless indicated to the contrary. For example, reference to a composition containing “a compound” includes one or more compounds. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.
All numeric values are herein assumed to be modified by the term “about,” whether or not explicitly indicated. The term “about” generally refers to a range of numbers that one of skill in the art would consider equivalent to the recited value (i.e., having the same function or result). In any instances, the terms “about” may include numbers that are rounded to the nearest significant figure.
Referring to
According to an aspect of the invention, there may be one, two, or three objective lenses 16 present. The device 100 illustrated in
Still referring to
The magnification device 100 illustrated in the exploded view of
Referring to
Lenses having magnification, i.e., collecting optics, produce an increase in energy or power density, as the beam diameter is reduced by the magnifying power of the optics, which, when viewing a laser beam through the lenses, may increase and result in hazardous exposure conditions to the eye. Although some laser systems are incapable of producing hazardous exposure conditions during normal operation, when viewing a beam through an optical instrument, for example, an eye-loupe, the hazards may be increased. In the optical systems of the magnification devices described herein, which collect light through the objective lens(es) 16 and eye lens(es) 18, the hazards from lasers are magnified, and can easily damage a person's vision since the cornea and lens focus the laser energy onto the retina. When viewing the laser from within the beam (intrabeam viewing) the hazard may be increased by as much as the square of the magnifying power of the optical magnification device.
Advantageously, the filtering system according to the invention blocks or filters the harmful transmission of electromagnetic radiation prior to becoming collected and increased by the optical system, and prior to entering the objective lens(es) 16, while being transparent to maximize visible light transmission. The filtering system, as illustrated in
The type of filters suitable for use according to the invention depend upon the radiation-emitting device being used during a procedure. For example, to prevent damage from a laser transmitting beams at wavelengths ranging between about 2600 to about 3000 nm would require a filtering system that blocks wavelengths in the above-described range. There are many different types of lasers available on the market suitable for use, some of which are capable of emitting more than one wavelength. Examples of lasers include, but are not limited to: argon fluoride, xenon chloride, xenon fluoride, helium cadmium, argon, excimer, erbium:yttrium-aluminum-garnet (Er:YAG), neodymium:yttrium-aluminum-garnet (Nd:YAG), erbium:chromium:yttrium-scandium-gallium-garnet (ER:CR:YSGG), laser diodes, titanium-sapphire, ruby, alexandrite, erbium, hydrogen fluoride, and carbon monoxide and dioxide.
Depending upon the laser used, the application, and the manner in which the laser is used, a protection factor, i.e., the Optical Density (OD), is calculated with respect to the filter(s). The higher the OD factor, the higher the attenuation. Filters suitable for use according to the invention are available from NoIR Laser Company, L.L.C. of South Lyon, Mich. The filters 20 and 22 may suitably be formed of polycarbonate.
As with devices 100 and 200, the filtering system includes an exterior filter lens 20 mounted to the distal open end 12 of the housing 310a. The filter lens 20 closes the distal open end 12 of the housing 310a. The filtering system also includes a second filter lens 22 mounted adjacent to the proximal open end 14 of housing 310c. A prescription or plano lens 24 is mounted to and closes the proximal open end 14 of housing portion 310c. As described above, the second filter lens 22 is provided to ensure that no harmful radiation reaches the user's eyes through any of the lenses (objective or eye lens(es)) of the magnification device.
In this aspect, spacers 28 are used to separate the various lenses 16 and 18. For example, a spacer 28 is illustrated in
In the Keplerian optical system, the one or more objective lenses 16 may be substantially circular, or could be rectangular, and may include, but are not limited to, convex, biconvex, plus convex, doublet plano-convex, doublet bi-convex, and other suitable precision magnification lenses. The device 300 illustrated in
The device 300 of
Referring now to
As illustrated in
According to an aspect of the invention, the filtering system attenuates wavelengths from a radiation-emitting source, for example, a laser, in the range of about 190 to about 400 nm. In another aspect, the filtering system attenuates wavelengths in the range of about 730 nm to about 760 nm, in the range of about 785 nm to about 1090 nm, and in the range of about 2700 nm to about 2950 nm. According to another aspect of the invention, the filtering system attenuates wavelengths at about 10600 nm. It should be understood that additional wavelengths may be filtered, as the above ranges of wavelengths is not meant to be exhaustive.
Advantageously, the magnification devices according to the invention block or attenuate harmful wavelengths of radiation, including laser light, whether visible or invisible, and provide magnification at 2.5×, 3.5×, 4.5×, and 6.0×. It should be understood that other magnifications may also be provided.
The invention has been described with reference to specific embodiments. One of ordinary skill in the art, however, appreciates that various modifications and changes can be made without departing from the scope of the invention as set forth in the claims. Accordingly, the specification is to be regarded in an illustrative manner, rather than with a restrictive view, and all such modifications are intended to be included within the scope of the invention.
Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. The benefits, advantages, and solutions to problems, and any element(s) that may cause any benefits, advantages, or solutions to occur or become more pronounced, are not to be construed as a critical, required, or an essential feature or element of any or all of the claims.
