IE20210088U1 - Slit lamp For ophthalmic applications - Google Patents

Abstract

The present innovation relates to a slit lamp for the inspection of the eyeball and related appendages and the evaluation of the anatomical and functional state of the eye, in which an improved unit is included for controlling the position of the relative mirror unit.

Description

SLIT LAMP FOR OPHTHALMIC APPLICATIONS DESCRIPTION The present innovation relates to the field of ophthalmology, and in particular that of instruments for observing the eye of a patient as a support for the diagnosis of ocular diseases. More specifically, the innovation relates to a slit lamp for the inspection of the eyeball and related appendages and the evaluation of the anatomical and functional state of the eye.

Such an instrument essentially comprises a lighting unit and an observation unit with which variable magnifications can be set, i.e., a microscope, both supported by a frame. The latter, starting from a base for resting on a horizontal plane, rises supporting the aforementioned units with expedients which also allow the units to rotate around a vertical rotation axis. In the lighting unit, arranged in an elevated position, the light beam is optically “closed” in known manners, creating a light line, suitable for viewing corneal sections and which for this purpose, projected vertically downwards, is deflected horizontally towards the patients eye through an underlying mirror unit.

In most situations, the focal point of the light and the observation centre coincide, as both focal plane and position. However, in conducting some exams, such as in particular so-called “scattering sclero-corneal illumination“ and “indirect retro- illumination” it becomes necessary to decentralise the lighting beam. In practice, the lighting beam is intervened on so as to move the focal point, distancing it from the observation centre, towards the inside of the eye.

In practice, such result is reached in the known slit lamps by virtue of a so-called tilting of the slit emitting the light radiation, the result of a rotation around the vertical axis thereof of the entire support tower of the lighting unit 1, controlled through a knob.

In practice, this tilting axis coincides with the output axis of the lighting beam from the lighting unit and represents an alignment axis between the unit itself and the mirror unit. Since such a unit is bulky and heavy, such a movement is relatively difficult, as it is difficult to ensure the desired controllability and accuracy.

In some other slit lamp models, constructions have been implemented which are capable of obtaining the decentralisation of the lighting beam from that of observation in a more comfortable, reliable and precise manner with respect to what is made possible by the tilting operation of the lighting unit as described above.

The present innovation provides a solution which, by virtue of a renewed configuration, allows to obtain further increased use advantages with respect to those of any known solution.

Such a result is therefore achieved by the slit lamp for ophthalmic applications according to the present invention, which has the essential features of the appended claim 1.

The innovation will now be illustrated more in detail with the description that follows of an embodiment thereof, provided by way of non-limiting example with reference to the accompanying drawings in which: - figure 1 is an axonometric view of a slit lamp according to the invention; - figure 2 is a section conducted on a vertical plane passing through the tilting axis of the lamp of figure 1, in the area of the mirror unit and showing only the significant parts in relation to the innovation; and - figure 3 is a section of the lamp conducted according to the plane Ill-Ill of figure 2.

With reference to said figures, a slit lamp according to the invention comprises a lighting unit 1 and an observation unit 2, both supported by a frame generally indicated with 3. The latter, starting from a base 31 for resting on a horizontal plane, rises supporting the aforementioned units with devices which also allow the movement, in particular rotation, of the units around a vertical rotation axis Z. In the lighting unit 1, arranged in an elevated position, the light beam is optically “closed” in known manners, creating a light line, suitable for viewing corneal sections and which for this purpose, projected vertically downwards, is deflected horizontally towards the patients eye through an underlying mirror unit 4.

The lighting unit 1 is affected by a so—ca||ed tilting movement with respect to the vertical axis Z’ thereof which, however, does not involve the entire support tower 32, which is actually fixed. The mirror unit 4 alone is rotatable around the tilting axis Z‘, with respect to the support tower 32 which is precisely mounted fixed in relation to Z’, with respect to the remaining part (base) of the frame, remaining bendable around the main rotation axis Z.

To this end, the mirror unit 4 is mounted on the tower 32 through a hinge joint 5 which may for example include a pin 5a with which the mirror unit 4 is integral, and under this a cup-shaped base 5b, the pin rising along the tilting axis Z‘ with rotatable connection from the contiguous portion of the support tower 32.

A screw 6 with a manually operated knob 6a is then included on the tower 32 with the elongation axis thereof angled with respect to the horizontal plane (or more generally plane XY orthogonal to the axis Z‘) to exercise a locking action on the pin 5a, by mechanical interference, to prevent rotation once the desired positioning has been obtained. The angle or of the screw 6 is preferably about 20°-40° measured between the aforementioned plane passing through the engagement point between the screw and the pin, and the elongation axis of the screw which starts from such a point, with a descending trend towards the base 31 of the lamp.

The locking screw 6 advantageously also has a repositioning function of the pin 5a. In fact, the screw works with an angle which allows it to create a pressure on the pin so as to push it upwards. This means that, with the pressure thereof, it can remove all axial clearances and therefore confer more centring stability. The outer surface of the pin 5a has, in the region in which the screw 6 lies, a cavity 5c for the engagement of the spheroidal or in any case cap-shaped tip 6b of the screw 6. Such a cavity, seen in horizontal section as in figure 3, has a bottom with a V-shaped profile and the pressure engagement with the spheroidal end of the screw 6 results in a precise centring of the mirror. Therefore, it is not necessary to rotate the unit 4 to recover the centring, but the re-screwing of the screw 6 is sufficient to automatically recall the desired centring.

The desired tilting movement functional to a required decentralisation of the lighting beam (correlated to each other due to an angular variation) can be easily obtained by simply rotating the mirror unit 4 through the relative joint 5. Only a light component of reduced size is rotated, considerably facilitating the actuation, making it reliable and not subject to wear or failures (since the stresses are lower), and also allowing the operator, in addition to reduced effort, greater sensitivity, precision and prompt response in positioning. In general, the quality of the adjustment, and therewith of the diagnostic examination, will be increased due to the drastic reduction of the movement inertia. With the oblique screw locking system 6 according to the innovation, greater stability of the assembly is then achieved with respect to the problems of axial and rotational clearances.

Therefore, with a constructively simple expedient, which indeed goes in the direction of an overall simplification of the instrument, a tangible advantage of use is achieved which further improves what has already been provided by the known art.

As said, the innovation is not limited to the embodiment described and illustrated above, but comprises any execution variant thereof.

Claims (1)

1. CLAIMS A slit lamp comprising a support frame (3) with a support base (31), a lighting unit (1) integral with a support tower (32) of said frame (3) which rises along a tilting axis (Z‘), an observation unit (2) in turn supported by said support frame, and a mirror unit (4) mounted on said support tower (32) in alignment with said lighting unit (1) along said tilting axis (Z‘), wherein said support tower (32) is fixed to the rotation around the tilting axis (Z‘) with respect to the rest of the frame (3), said mirror unit (4) being mounted on said support tower (32) through a hingejoint (5) so as to allow a rotation thereof with respect to the tower (32) around said tilting axis (Z‘) wherein means are provided for controlling the rotation of said mirror unit around said tilting axis (Z‘), comprising selective locking means (6) of the rotation in the desired position, wherein said selective locking means comprise a screw (6) arranged on said support tower (32) with the elongation axis thereof angled with respect to a plane (XY) orthogonal to said tilting axis (Z‘), adapted to mechanically interfere with said hinge joint (5) through a tip thereof (6b). The lamp according to claim 1, wherein said screw (6) has said elongation axis descending starting from said tip (6b) towards said base (31); and/or wherein the angle (or) between said elongation axis of said screw (6) and said plane (XY) is between 20° and 40°. The lamp according to claim 1 or claim 2, wherein said hinge joint comprises a pin (5a) which rises along said tilting axis (Z‘), with which said mirror unit (4) is integral, and coaxially to a cup-shaped base (5b), said pin (5a) being rotatably connected to a contiguous portion of said support tower (32). The lamp according to claim 3, wherein said screw (6) included on said support tower (32) is adapted to exert the locking action on said pin (5a) by mechanical interference between said tip (6b) and a cavity (5c) formed on the lateral surface of said pin (5a); or wherein said screw (6) included on said support tower (32) is adapted to exert the locking action on said pin (5a) by mechanical interference between said tip (6b) and a cavity (5c) formed on the lateral surface of said pin (5a), wherein said cavity (5c) has a bottom with a V—shaped profile seen in section according to a plane orthogonal to said tilting axis (Z‘)_ The lamp according to any one of the preceding claims, wherein said tip (6b) of said screw (6) has a spheroidal or generically cap—|ike shape; and/or wherein said screw (6) has a manoeuvring knob (6a) at the opposite end with respect to said tip (6b), outside said tower (32).