JP2558975Y2 - Short distance optometry device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION The present invention relates to a short-distance optometry apparatus which is held at least one predetermined distance by a subject during optometry, and has a large number of optometry fields to be irradiated. Format.

2. Description of the Related Art A short-range optometer is used to determine whether there is short-range visual impairment. Various near-field optometry devices are known for optometry and, in some cases, for obtaining vision correction values.

In order to determine the lenses of the reading glasses, it is common for the subject to hold the short-distance optometer at a fixed distance suitable for his / her reading habit during optometry. In such a known short-distance optometry apparatus, the optometry field provided on the swivel optometry disc is illuminated by a tubular incandescent lamp arranged inside the short-distance optometry apparatus. In order to confirm the predetermined optometry distance, two light beams of another incandescent lamp are projected on the forehead of the subject. The predetermined optometry distance, which is usually 40 cm, is the distance when both rays overlap.

A disadvantage of this close-range optometry device is that the illumination density of the optometry field is too low. Therefore, the contrast condition during the optometry does not match the natural condition or the normal condition. The spectrum configuration of the optometry light also does not match the configuration of the spectrum of the normal light, and the optometry light has an excessively large ratio of red light. Since the refracting power of the eye is related not only to the wavelength but also to the intensity of the optometry light, these measurement conditions must be considered when determining the vision correction value after the optometry. Further, when the optometry apparatus is used for a long time, the optometry apparatus is heated by the incandescent lamp, so that the optometry disc may be damaged.

In the optometry apparatus described in DE 3102381, the image receiving surface of a color picture tube is used as an illumination source. Since the optometry apparatus becomes very large and heavy by this means, the optometry apparatus is used only as a desk apparatus, and the subject cannot hold the optometry apparatus during the optometry. Further, since a color picture tube is used, the production cost of the optometry apparatus becomes high.

The problem to be solved by the invention The problem to be solved by the invention is to improve a near-field optometry device of the type mentioned at the outset, so that the optometry field is similar to normal daylight in terms of brightness, contrast and spectral composition Is to do so.

Means for Solving the Problem In order to solve this problem, in the configuration of the present invention, a fluorescent lamp is provided as a light source for irradiating the optometry field, and the fluorescent lamp is provided on both the front side and the back side of the short distance optometry apparatus. An optometry field is provided, and a fluorescent lamp is arranged between the optometry fields on both sides to simultaneously irradiate the front and back optometry fields.

The optometrist field is illuminated with a sufficiently high luminous intensity due to the large illumination power of the fluorescent lamp. As a result, an eye test can be performed in a normally illuminated optometry room. There are many types of fluorescent lamps whose light has a spectral composition of daylight in terms of spectral composition, and these can be easily obtained in the market. The heat problem does not occur with fluorescent lights.

In a short-range optometer held by a subject, the same light spectrum relationship as in a long-range optometer can be obtained only by using a fluorescent lamp for irradiating the optometry field. Thus, the optometry results can be compared directly with one another.

Some remote optometrists are equipped with fluorescent lamps to illuminate the optometrist field, but these are wall-mounted optometrists with a size of, for example, about 60 x 60 cm.
m, since the weight is about 34 kg, the subject cannot hold it during the optometry. In the case of such a large optometry apparatus, the fluorescent lamp can be easily incorporated by using a commercially available fluorescent lamp mounting apparatus.

On the other hand, in the case of a hand-held optometer having a size substantially equal to the size of a book, it is not easy to incorporate a fluorescent lamp due to space limitations. Furthermore, from the viewpoint of safety of the optometry apparatus, in such a hand-held optometry apparatus, only a lamp for low voltage should be used.

The use of a gas discharge lamp in combination with an electronic light valve surface instead of a color picture tube to illuminate the optometry field is described in DE 320 238 A1 described above.
No. 3,133,608, which is an additional patent to No. 1. However, also in this desk apparatus, the size and weight of the optometry apparatus have only secondary significance. Furthermore, in the optometry apparatus described in DE-A-3133608, optometry conditions similar to daylight are not created. This is because it has been proposed to use gas discharge lamps instead of using incandescent filament lamps.

According to the present invention, the optometry fields are provided on both the front side and the back side of the short-distance optometry apparatus, and the optometry fields on both sides are illuminated by the fluorescent lamp arranged therebetween, so that the optometry is performed. The use of both sides of the device is possible, doubling the optometric ability. The reason why both sides can be used is that the illuminating power of the fluorescent lamp is sufficiently large as described above.

In order to equally illuminate the optometrial fields on both the front side and the rear side, a reflector is provided. In this case, two V-shaped reflectors are arranged on the side of the fluorescent lamp, with their respective tips facing the fluorescent lamp.

Fluorescent lights must be quick and easy to replace. Even if the optometrial fields on both sides, front and rear, are provided on rotatable discs, one of both discs can be easily replaced without tools to allow quick replacement of the fluorescent lamp. Make it removable. For this purpose, one disk is fixed to the rotating shaft by a spring-loaded clamp. The removable disk can be replaced, if necessary, with another disk for another inspection.

In order to keep the optometry device at two defined optometry distances, an optical distance display is provided. This distance display device projects three light beams on the forehead of the subject. Since the fluorescent lamp emits more light than is necessary for irradiating the optometry field, the light of the fluorescent lamp can be used for distance display. Such a light beam may be, for example, an image of a gap illuminated by a fluorescent lamp. The defined optometry distances are respectively generated when two of the three rays overlap. When both sides of the optometer are used, such a distance display device is provided on both the front side and the back side.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a short-distance optometry apparatus which can be held by the reference numeral 1, and is provided with a U-shaped member 2 which can be turned. The main body of the short distance optometry apparatus 1 is supported by a U-shaped member 2 held by the subject during optometry.

The short-range optometry apparatus 1 has one optometry disc 3 and 4 in two different planes, respectively, and these optometry discs 3 and 4 are provided with a plurality of transparent optometry fields of the same size. I have. In the drawing, of these optometry fields, only five optometry fields 3a to 3e of the front optometry disc 3 are shown. Each optometry field 3a-3e has a different optical test pattern.

Both irradiation discs to illuminate the optometry field
One fluorescent lamp 5 is provided between 3 and 4. The fluorescent lamp 5 is a low-voltage fluorescent lamp, and its length is about 15 cm. The current is supplied from an external power supply unit.
For this reason, the weight of the short-range optometer is kept small, and at the same time, the safety of the short-range optometer is guaranteed. This is because only a low voltage is supplied to the short distance optometer. The lamp sockets 13a and 13b are extremely space-saving,
It consists of two spring-loaded sheets of copper, which are provided with guide holes for receiving the contact pins 16a, 16b of the fluorescent lamp 5.

In order to illuminate the optometry field equally, one V-shaped reflecting mirror 6, 7 having a white surface 6b, 6c, 7b, 7c is provided on each side of the fluorescent lamp.

As can be seen from the cross-sectional view of FIG.
The tips 6a and 7a of the are directed toward the fluorescent lamp. The front surfaces 6b and 7b of both reflecting mirrors guide the light emitted from the fluorescent lamp 5 from the side toward the optometric disc 3 on the front side. The rear surfaces 6c, 7c of the reflecting mirrors 6, 7 guide the light emitted from the fluorescent lamp 5 from the side toward the optometry disk 4 on the rear side.

As shown in FIG. 1, both optometry discs 3, 4 are fixed to an axis 8 perpendicular to the plane of the drawing. A drive is provided for rotating the two optometry discs 3 and 4 together and comprises a drive sheave 10, a belt 9 and a driven sheave 11 fixed to the shaft 8. ing. The optometry discs 3 and 4 are rotated by the drive belt wheel 10, and the desired optometry field of the front optometry disc is positioned in front of the fluorescent lamp 5 and the reflecting mirrors 5 and 6,
At the same time, a desired optometry field of the back-side optometry disc is positioned on the back side of the fluorescent lamp 5 and the reflecting mirrors 5 and 6.

The fluorescent lamp is positioned at an angle to the positioned optometry field, and
The surface directly illuminated by the fluorescent light is the brightest.

The positioned optometry field can be viewed from the front through the eyepiece opening of the cover, not shown, or can be viewed from the rear through the eyepiece opening on the rear side of the device casing. Depending on which side the subject faces the short distance optometry device, the subject can see different optometry fields.

The front optometric disc is fixed to the shaft 8 by two spring-biased clamps 12a and 12b. These clamps 1
2a and 12b can be easily separated from the shaft 8 against the biasing spring force. Next, the fluorescent lamp 5 is connected to its socket 13a,
You can remove it from 13b and take it out. After the replacement of the fluorescent lamp, the optometric disc 3 is easily fixed to the shaft 8 again. It is also possible to replace the front optometry disc 3 with another optometry disc. Such additional optometry discs may be provided with optometry codes for children, for example.

The three V-shaped reflectors 17a, 17b, 17c and the incandescent lamp 14
It is used to adjust the prescribed optometry distance.
Each of the three V-shaped reflectors 17a, 17b, 17c has a pointed end directed toward the incandescent lamp 14 to redirect a portion of the light of the incandescent lamp 14 forward and backward. 40cm
At the optometry distance described above, the lights that are turned from the first reflecting mirror 17a and the second reflecting mirror 17b among the V-shaped reflecting mirrors 17a, 17b, and 17c are oriented so as to overlap. In the case of the second optometry distance of 55 cm, the first reflecting mirror 17a and the third reflecting mirror 17c
The lights that are changed in direction are overlapped. The reason these two distance values were chosen is that the typical reading distance is about 40 cm, and the typical eye distance when working while looking at the image receiving surface is about 55 cm with respect to the image receiving surface. It is.

In this embodiment, one unique incandescent lamp 14 is provided for distance indication, which can be switched off by a switch 15. However, it is also possible to use a part of the light emitted from the fluorescent lamp 5 for displaying the distance. Thereby, the incandescent lamp 14 can be omitted.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a front view of a short-range optometry apparatus according to the present invention, and FIG. 1a is Ia-Ia of FIG.
FIG. 3 is a partial cross-sectional view of the short-range optometry apparatus taken along a line. DESCRIPTION OF SYMBOLS 1 ... Short-range optometry apparatus, 2 ... U-shaped member, 3 and 4 ... Examination disc, 3a-3e ... Optometry field, 5 ... Fluorescent lamp, 6 and 7 ... Reflector, 6a and 7a ... Tip, 6b and 7b ... Front face, 6c and 7c ...
Rear surface, 8 ... shaft, 9 ... belt, 10 ... drive belt wheel, 11 ... driven belt wheel, 12a and 12b ... clamp, 13a and 13b ... lamp socket, 14 ... incandescent lamp, 15 ... switch, 16a and 16b ... contact Pin, 17a ・ 17b ・ 17c… V-shaped reflector

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hermann Schurle Aachen Bischau-Fischer-Strasse 110 Germany (56) References JP-A-60-171030 (JP, A) JP, Y1)

Claims (3)

(57) [Scope of request for utility model registration] In a short-distance optometry apparatus which is held at least one predetermined distance by a subject during optometry and has a plurality of optometry fields to be irradiated, an optometry field (3a to 3a) is provided. A fluorescent lamp (5) is provided as a light source for irradiating 3e). Optometrist fields (3a to 3e) are provided on both the front side and the back side of the short-range optometer (1).
3e) is provided, and a fluorescent lamp (5) is arranged between the optometry fields on both sides to simultaneously irradiate the front and back optometry fields (3a to 3e). Short distance optometry device. 2. The two V-shaped reflecting mirrors (6, 7) each having a pointed end (6a, 7a) directed toward a fluorescent lamp (5) in order to illuminate the front and rear optometry fields equally. )
The short-distance optometry apparatus according to claim 1, characterized in that is provided at a side of the fluorescent lamp (5). 3. Optometric fields on the front side and the back side are provided on rotatable disks (3, 4), respectively, and one of the disks (3, 4) is used for replacing a fluorescent lamp (5). 3. The short-distance optometry apparatus according to claim 1, wherein the first lens is detachably fixed to the rotating shaft by a spring-biased clamp.