DE1622014A1 - Reflector for lighting device or radiant heater - Google Patents

Description

'Pr. Walter Länghoff Munich, January 12, 1968

Patent attorney. _My - _ZßiQhen .

M ΰ η c h e η 8 1

Wissmaimstrisst 1 *

1622Q14

description

. to the patent application of the gentleman

Jean Planchon, 9 * rueChaptal, Paris 9 ^e ,

France

concerning

iteflektor for lighting device or radiant heater

Priority: January 12, 1967 ■ »France

The invention relates to a projector, in particular a reflector for lighting devices or radiant heating devices.

For manufacturing reasons, the known Heflectors have geometrically simple shapes, e.g. the shape of a truncated cone, a straight cylinder section with a circular, elliptical, rectangular or parabolic cross-section, in the form of a paraboloid, part of an ellipsoid or a ' Union of at least two of the simple geometric shapes mentioned above.

Such reflectors do not always provide a satisfactory one Radiation. Certain known reflectors produce a concentration of energy In one or more preferred directions, do not cause any energy distribution of the radiation

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a predetermined, desired regularity, for example a uniform irradiation of the entire extent of an irradiated zone.

In the known individual lighting devices are Curves of equal light intensity measured in one plane in generally concentric and the radiation increases from one Turn off the highest radiation intensity very quickly, whereby the Place the highest radiation intensity most often in the axis (Vertical) of the radiation source. With a light bulb of 75 watts you get at a distance of 30 cm from a working level in the axis of a reflector whose opening is parallel to the working level, with a Liehtstrom of 2600 Lux in the axis of the lightbulb a light intensity of 1000 lux in one Distance of 25 cm off this axis, of 600 lux in a distance of 33 cm off-axis and finally of only 200 lux at a distance of 52 cm outside the Axis. So if you have a part of 40 cm on the work surface If you want to illuminate width, so that its center is at a point of 400 lux light intensity, one of the edges of the Part at a point with 1000 lux light intensity, while the the other of its edges is at a point with a light intensity of about 100 lux. One half of the part. so points accordingly an average illuminance of around 200 lux, and while a viewer with one eye in his field of view is one Area seen, the mean lighting of which is much higher is the other than the mean illumination in the field of view

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Eye, this results in a different adaptation of the eyes, which results in a certain amount of fatigue. If one now also tries, by increasing the performance of the. Light source the illuminance of the less illuminated Increase half of the illuminated part, so this can the illuminance of the other half desi rope so strong be increased that it acts as a mirror and a glare causes eye fatigue,

In order to avoid this disadvantage, a diffusing screen is sometimes used under the lightbulb, thereby reducing the Illuminance becomes more even in the working plane, however, it also sinks noticeably on average, so that considerably higher illuminance levels are required to achieve sufficient illuminance Services have to be expended, which usually means the Application for single lighting is limited due to the high, generally required illuminance »

The subject of the invention is a reflector that has these disadvantages does not have «The reflector according to the invention has the shape a complex surface with a number of individual, simple " tarer reflective surfaces that are connected to one another at their upper and lower edges connected by continuity surfaces and which are connected by steps at their side edges are or vice versa, with the directions of the tangent planes

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on the reflective elementary surfaces are chosen so that the areas of the zone to be illuminated are illuminated by them adjoin or overlap so that a desired The regularity of the illuminance distribution results.

According to a further development, the reflector has additional surfaces on, those outside the zone to be illuminated have a lower value Generate illuminance to brighten the surroundings.

The invention is described below with reference to θchematiaeher drawings described in addition to several exemplary embodiments.

Pig »1 is a perspective view of the reflection of a linear filament at one point a mirror on a surface to be illuminated.

Figure 2 is a vector representation of radiation intensity of a point on a completely diffuse surface »

Fig. 5 shows the usable angle at which a frosted or opal light source from a point;. appears.

Figo 4 shows the image of a uniformly luminous Light source through the point of a mirror onto a surface to be illuminated.

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ORIGINAL IiSISPBCTED '

^ 5 ^ '. ■. 1-6220H

Fig. 5 shows the determination of the line of intersection of an elementary mirror dee projector with a horizontal one running through the center of the elementary mirror Level.

6 shows the determination of the center line of an elementary mirror of the protector with a running through the center of the same and through the light source vertical plane ο

Pig _e 7a shows the horizontal projection of the cutting lines of the protector in different horizontal planes and

7b shows the lines of intersection of the projector on vertical planes which run through the center of the light source and form different angles with the plane of symmetry of the projector, these lines of intersection being derived using the method according to FIGS. ₀ 5 and 6 "

FIG. 8 shows a section through one according to FIGS 7b constructed projector.

Figo9a. -,

and 9b show the beam path of the projector according to FIG. 8,

10 shows a further embodiment of a projector

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. ■.; For side lighting using a frosted or opal light source <,

Figures 11a, 11b and 12a, 12b

show projectors according to the invention, which partially give the light source in the form of a light bulb. '

Figure 13 is a sectional view of a decorative glass dome, which is partially formed in a certain way, so that it forms a reflector according to the invention "

Figo 14a and Hb show the lighting conditions on a fluorescent lamp _{or the like}

Figo 15a, 15b as well as 16a, 16b and 16c

show reflectors according to the invention for a fluorescent lamp ο

Figo 1 shows a light source in the form of a filament 1 a Light bulb, a plane mirror 2 and a surface to be illuminated 3o If one looks at any point P of the plane mirror 2 and the Hormale PH at this point P of the mirror as well as one Point S of filament 1, so is according to the law of reflection the angle of incidence SPN is equal to the angle of reflection NPR »Der Point R is therefore the mapping of point S onto surface 3 (Working surface), which is given by the infinitesimal mirror element P of the plane mirror 2 is caused. If one assumes that the

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OR [QINAL INSPECTED

> 7 ~ 1822014

Plane mirror 2 completely reflected, not diffuse reflected, the reflected beam PR is the only one the ray corresponding to the incident ray SF. One turns the same consideration for the other points of the filament. 1, this results in image 4 of the filament on the work surface 3, which is completely predictable = you can yourself now the plane mirror from a large number of elementary mirrors think composite, each of which depicts an image of the filament on the work surface 3, so that a Illumination of the same by an infinite number of mutually overlapping Images of the filament gives, where the illuminance at each point of the work surface 3 can be determined in advance

FIG _o 2 shows a vectorial representation of the light distribution in different directions by a non-reflective, completely diffuse point Qo there is according to this Barstellung the luminous flux normal to the surface in which the point Q is the value 1, it is apparent for one direction of 45 to the normal a value of 0.707 and for a direction of 60 ° to the normal a value of 0.5 ° For angles greater than 60 °, the intensity decreases very quickly »According to Pig _o 3 you can therefore calibrate when looking at an opalized incandescent lamp from a point P to the consideration of those points of the incandescent lamp whose normal to the incandescent lamp with the connecting line to the point P forms an angle of less than every 60 °.

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Pig, 4 shows the image of an opalized incandescent lamp 5 through the point P of the plane mirror? on the work surface 6, different rays being drawn in. ° If the The bulb of the incandescent lamp is spherical, the rays running to point P result in a circular cone, the tip of which is in the Point P lies, and the entirety of the reflected rays has completely defined generators which intersect the working surface 6 on an ellipse. This ellipse forms a central zone of high illuminance corresponding to the rays that are at a small angle with respect to the Normals on the lightbulb, proceed from the same » The central zone is surrounded by zones of decreasing illuminance corresponding to the locations of the bulb which a large angle between the normal and the connecting line to form the point P "

The problem with the production of a reflector with a predetermined distribution of the illuminance on an illuminated surface (work surface) consists in determining the illuminance on the work surface bu for each infinitesimal mirror, taking into account the nature and the position of the light source and the To determine the orientation of these mirrors in such a way that the portions of the lighting produced by these mirrors border one another or overlap so that the distribution of the lighting intensity is obtained.

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BATH ORIGINAL

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A practical method of determining the solution of a tin The particular problem is to determine the shape and dimensions of the areas to be illuminated at different points Image of the light source to determine which is reflected by reflection at the various infinitesimal mirrors that at previously determined points on the surface of the reflector lie and have the desired dimensions, and then the Tendencies to determine the various infinitesimal Mirrors must have so the images of the light source Adequately adjoin one another or meet one another at work Overlay to achieve the desired lighting «.

The Figo 5 and $ show how advertising performed this calculation, the pot In these figures ist'eine as horizontal angenom ^ mene working level 8 drawn and a light source 9 in the form of an incandescent filament <> can also be seen the beam path is one of the bulbs point S outgoing light beam »which is reflected on an infinitesimal plane mirror at the point P of the reflector and hits the point R of the working plane 8 *"

Pig, 5 also sees a plane 10 running through the point P parallel to the work surface 8 "which is also horizontal, as well as a vertical plane 11 on which the points S and P lie". This plane forms an angle H with the vertical plane 12, which passes through the point S and forms a reference plane _Q. On the ray PR is © at point B

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drawn in such that the distance PB is equal to the distance PS, and the points BS are connected to one another by a straight line. According to the law of reflection, the normal PU lies on the point P of the infinitesimal plane mirror in the plane defined by the points S, P and R and forms the bisector through the tip P of the isosceles triangle SPB ₀ This bisector intersects the line SB at the point M » In Fig. 5 the orthogonal projections S, M ₁ and B _{1 of} the points S, M and B are plotted on the plane 10 and it can be seen that the point KL forms the center of the segment B ₁ , S ₁ , d «h <, that the line PM _{1 forms} the bisector of the triangle S ₁ PB ₁ through the apex P =

If the line of intersection of the infinitesimal plane mirror at the point P with the plane 10 is represented by a straight segment 13, it is evident from the construction of the point M ₁ that the segment 15 is orthogonal to PM ₁ = it follows that with the determination of the Direction of the straight line PM ₁ in the plane 10 has also derived the path to the plane of the infinitesimal plane mirror at the point P by calculation »The relative positions of the points S, P and R after their determination also result in the distances PS and PR, the angle H of the dihedron running through the vertical planes 11 and 12, the angle SPS ₁ (- d), which is otherwise equal to the angle of the segment SP with the _{horizontal plane running through S, the angle S 0} P ₀ R, where S _Q and P _{Q form} the orthogonal projections of S and P onto the working level 8

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,: ORiGiNAL INSPECTED

Angle PEP ° and finally the angle S ₀ P ₀ R, which is equal to the angle A, increased or "decreased" by an angle D, which defines the angular position of the point · R with respect to one running through V _Q and parallel to the plane 12 Tertical plane determines »The angle PRP ₀ is denoted by r and is equal to the angle BPB ₀ In the right-angled triangle PBB ₁ with the right angle at B- the following relationship applies

as. P B cos r

= PS cos r

Further, since the angle S ₁ PB ₁ is equal to H + D, the triangle S can be in the plane PB 10 _{1 1} construct and, therefore, the point H ₁ find _o The size of the Winkele r can be ₀ with R in the right-angled triangle PP the right angle at P _Q through

tgr «PP ₀

the equation

ο
can be found and the size of the side PS ₁ can be found in the right triangle PS ₁ S by the relationship PS ₁ = PS cos

It can be seen in Figure "6 at Μ 'and B _2, the orthogonal Pro; the points M and B injections to the plane 11 and as with Figo 5 is the straight line PM _2, the Seitenhalbierende through the point P of the triangles PS ₂ S," Since you knows the side PS in this triangle, the side PB ₂ can be calculated, which is determined in the triangle PB ₂ B by the equations

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PB ₂ β PB cos γ
PB ₂ = PS cos γ

where γ is the angle RPR _Q and the point R _{Q forms} the orthogonal projection of the point R onto the plane 11. It can be shown that the angle γ can be calculated from the following equation

. sin γ = cos r sin (H + D) (1)

If α ₌ the angle P _Q PR _Q is in the right triangle PP ₀ R ₀ , then the relation applies:

P ₀ R ₀ = PP ο tgo (2)

In addition, the following equation applies to the triangle P _Q R ₀ R, which is right-angled at R:

P ₀ R ₀ = P ₀ R cos (H + p) (5)

Finally, the equation applies to the right triangle PP _{Q R}

P ₀ R = PP ο cotg r (4)

The relationships (2), (5) and (4) result

tg α = cos (H + D) cotg r (5)

For the right triangle PR _Q R one obtains the relation!

R ₀ R »PR sin γ (6)

Lt at de
equation

The same applies to the right-angled triangle R _Q P ₀ R

R ₀ RVH ₀ P ₀ tg (H +, D) (7)

Furthermore, in the right triangle R ₀ P _Q P:

^P o ^R o - ^PP o te «(8)

Finally, the equation applies to the right triangle PP _{0 R:}

PP ₀ = PR a r (9)

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The equations (6), (7), (8) and (9) result

sin γ «tg (H + D) tg α sin r (10)

and by replacing tangent with that in equation (5) ■

given value *

sin γ - tg (H + D) sin r cos (R + D) cotg r (11)

where by replacing the tangent · ^ and cotangent expressions by the corresponding sine »and cosine expressions and by simplifying?

sin Y = cos r sin (H + D) (12)

which is equal to equation (1)?

If one knows the relative positions of the points S, P and R, ie the angles r * H and D, PB ₂ can be calculated and transferred to the straight line PR _Q , which can be constructed geometrically if the angle α is known with the help of the equation (5) _o One can therefore determine the position of the point M «and thus the straight line PM _{2 P. Therefore, the segment 14 which is at right angles to the straight line PM 2} at the point P can be constructed» which forms the intersection of the plane 11 and the infinitesimal plane mirror the point P forms and causes the reflection of the beam SP in PR *,

If under these conditions a point S of the light source, a Point R of the zone to be illuminated and a point P Buf the Surface of the reflector is assumed, the mirror plane can be determined which is the desired at the point P. Reflection of the beam S P in the beam PR causes, where

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this determination is made by constructing the line segments which correspond to the lines of intersection of the mirror with the horizontal plane passing through the point P and with the vertical plane passing through the points P and 3. Since the angle at which the filament 9 of the light bulb appears from point P is known, the shape of the image of the filament on the work surface and the relative contribution to the illumination of the same can be determined , about 160, on the surface forming the reflector, the positions of the infinitesimal plane mirrors can be determined, which are located at these points, so that the images produced by them on the zone to be illuminated result in a predetermined lighting distribution.The entire surface of the reflector is then located represent as a complex reflective surface, which is created by placing flat mirrors next to each other, which are constructed as indicated above and adjoin each other at obtuse angles or more or less acute angles, so that a continuous illumination of the working plane is created due to the extension of the infinitely many images that form each mirror plane the infinitely many infinitesimal _{mirrors o} In principle, the influence of the steps is reduced and the accuracy of the lighting distribution on the step to be illuminated is increased by replacing the plane mirrors with concave mirrors that lie tangentially at every point P of the plane mirror ο determining the curvatures of the concave mirrors takes place graphically or by calculation according to methods known per se.

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ORIGINAL INSPECTED

7a and 7b show the result of one according to the above Procedure carried out investigation, the'kurven according to

7a section lines between the inner surface of the reflector and form horizontal planes on different sides and. the curves according to FIG. 7b, intersection lines between the inner surface of the reflector and vertical planes passing through the The center of the light source run and with a vertical, reference plane, which in this particular case the symmetry of the projector forms crossing angles, with the intersection lines pointing down from the symmetrical "The curves according to Fig, form a series of curved segments which, according to the procedures described above are determined and mutually by one another Connections are connected, which öön steps between the correspond to corresponding surfaces. The curves according to FIG. 7b are continuous and result from being strung together of curved segments, in Figo 7a are only those Curves for one half of the reflector given as the curves for the other half symmetrical to the axis AA liegem bei Figo 7a, the line 15 denotes the line of intersection of the inner surface of the reflector with that through the center point S of the light source -progress ending horizontal plane «this line forms a series of curved segments strung together are by curvilinear connectors so that line 15 forms a continuous concave curve except at the point 16, which corresponds to the connection between the front part and the rear part of the reflector, with different Dimensions in the form of a large scale, which are essentially

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runs at right angles to the adjacent parts of curve 15. FIG »7a further shows the lines of intersection of the inner surface of the reflector with horizontal planes at different heights above and below the aforementioned plane _O of the curve 17 is part of a 8 cm higher level, the curve 16 cm to a 16 higher level, the curve 19 to one 8 cm lower. Level and curve 20 to a level 16 cm lower »

These curves point at the level of step 16 of curve 15 comparable levels 21, 22, 23 and 24 on o also form curves 17, 18, 19 and 20 are a succession of curved ones Segments that are not strung together like the curve 15, but with one another by small paragraphs 25 or 26 are connected o

The curves of Figure 7 _o form a sequence of curved segments. The curve 27 corresponds to the line of intersection of the rear part of the reflector with a vertical plane which runs through the center of the light source and which forms a zero angle with the angle of symmetry

The curve 27 ends in an inclined part 28 and downwards a circle 29 which corresponds to the flanged edge of the reflector, to increase the strength of the same, while the curve is bent in the upper area and a flansoh 30 forms, which corresponds to the upper edge of the reflector and a causes sufficient firmness of the geese. The curve 51

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speaks of the cutting line of the front part of the reflector with one running through the center point of the light source vertical plane coincident with the plane of symmetry of the reflector forms an angle of 20 ° and is otherwise similar like curve 27e The same applies to curves 32, 33, 34 * 35 and 36, the cutting angles of 40, 65, 75, 80 and 115 ° correspond, with the sloping areas at the lower part and the areas converging at the top more or less differ"

The curve 37 forms the intersection of the front area of the reflector with the plane of symmetry «The entire drawing represents the elevation of the reflector and determines completely the elementary mirrors that make up the inner surface of the Reflector is composed "

Pig = 8 shows a section through a projector according to FIG the elevation and the second elevation of ligv 7a and 7b isto The light source is a light bulb 38 »whose axis with the vertical axis of the projector at an angle of approximately 15 ° forms «, the rear surface 39 of the reflector is at its lower Edge 40 beaded and curved like a hairpin at its upper edge 41, and the front side 62 is with its lower edge 43, while the upper edge 45 is bent like a hairpin o The emanating from the light source Light rays fall on the rear surface 39 of the reflector and are reflected by this onto the work surface <>

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Most of the rays falling on the front surface 42 are reflected towards the back surface that they are essentially reflected back onto the work surface by the zone in the region of the point 46. A small number Rays of light that strike the front surface 42, in particular on the area 47 »are reflected backwards, but past the surface of the reflector and form an ambient lighting» Furthermore, certain rays that hit the side zones of the reflector are used for ambient lighting the actual work surface is used.

FIGS. 9a and 9b show the lighting distribution one level when using a projector according to FIGS. 7a, 7b and 8ο The projector 48, which is shown in FIG. 9a in plan view is shown and in Figo 9b in side view, is arranged at a certain height above a horizontal surface and concentrates a substantial part of the light energy to a beam 49, which is limited by the outer rays 50 and 51, which an angle of about 30 to 40 or "form 15 to 20 ° with the horizontal plane" This light energy is evenly applied to the work surface 52 over a approximate rectangle distributed The work surface is on the one hand surrounded by a zone 53, which between the working plane and the projector, and may further include that area of the horizontal plane which is below the Projector and in which the illuminance is less than or equal to the illuminance of the work surface 52 »

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Furthermore, 3 zones -54, 55 and 56 are seen in which the Illuminance decreases rapidly from the work surface 52 " ,

Zone 57 behind the projector ensures ambient lighting « Just one height of the reflector above the horizontal At the level of about 30 cm, the left edge of the work surface 52 is about 35 cm from the vertical the projector and a corresponding one on its right edge Distance of 95 cm and a width of about 45 cm over the entire surface »The illuminance is practical even

10 shows a further embodiment of a projector according to the invention, which is preferably suitable for the use of opalized or frosted incandescent lamps. Inside the outline 58 _t delimiting the outer surface of the projector, mirror surfaces 59 »60, 61, 62, 63, 64, 65 and 66 are arranged, which are separated by steps 67, 68, 69, 70» 71 and 72 , which are distributed over the side surface of the projector o In addition, additional mirrors 73, 74, 75, 76 and 77 are used on the floor, which are connected by steps 78, 79 and 80 to utilize the radiation running towards the bottom of the projector. These additional mirrors direct the light radiation onto the work surface, while the additional mirrors 81 and 82 emit the light radiation coming from above through recesses in the upper part of the projector as ambient lighting O

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Mirrors 83 can also be arranged below the light bulb be that prevent the light emitted downwards perpendicular below the projector to a too strong, undesirable lighting result, so that the light through the opening 84 is directed onto the work surface. Furthermore, mirrors 85 can be arranged below the light bulb, which direct the light directly onto the mirrors 62 or 75, from where it ended up on the work surface

Figures 11a and 11b show another embodiment a reflector 86 which partially surrounds a light bulb 87, the whole being housed in a lampshade 88 which may or may not be translucent and which is primarily intended to have a decorative or shielding effect The ZcBo reflector can be produced by pressing from a high-gloss aluminum plate that is anodically oxidized is «You can reach with this reflector in a side Direction a very pronounced directional effect in comparison to a lamp that is not provided with this reflector *

Figures 12a and 12b show another embodiment a reflector 89 which partially surrounds a light source and which can be used to illuminate showcases

13 shows in section a decorative glass dome which can be made by molding or pressing and the lower area 90 of which is produced on a core mold,

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is that corresponding to the inner surface of the reflector according to Figo 7a and designed 7b, wherein the inner surface diesesΐ lower portions 90 with a reflective coating is provided, which can be vacuum deposited about, so that this region _β as a typical reflector acts The upper portion is not provided with a reflective material and remains translucent and contributes to the ambient lighting «These glass domes can be used as bed lamps, work lamps or also as wall lamps«

Pig 14a and b are similar to Fig. 3; However, Y refer to fluorescent lamps »These figures show the fixed angle at point P at which the light rays emerging from fluorescent lamp 92 appear, again based on a radiation angle of up to 60 °. As already mentioned, these rays mainly contribute to the lighting ο The main radiation, which is reflected from the point P in the direction of the work surface to be illuminated, corresponds to these rays of high intensity and is contained in a cone, the tip of which is at P and the one having cross section in the form of a very elongated oval whose central zone of high luminous flux can be completely determined with respect to the size, shape and direction. The various reflective surfaces of the reflector can be designed according to the invention in such a way that favorable lighting for office purposes, warehouses, classrooms and the like results «,

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The fig ο 15a and 15b show a projector 93 according to the Invention for distributing light from a fluorescent lamp 94 over a predetermined work surface «,

FIG »I6a, 16b and 16c show a further embodiment of a reflector for fluorescent lamps _o The inner surface 95 of the reflector has a number of elementary reflecting surfaces, the Carre 'are arranged like." The orientation of the elementary projection surfaces allows the image of the light source to give a very inclined orientation on the work surface in relation to the axis of the lamp up to a right angle in relation to the axis of the fluorescent lamp _B. of the people in the middle of the hall =

The reflectors according to Pig «15a, 15b and 16a, 16b, 16c can be provided vertically under the fluorescent tubes with opal panels of suitable dimensions to the to cover direct radiation from the fluorescent lamp *. The reflectors can also be made of a transparent sheet Material to be closed »

The reflectors themselves can be known per se

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Manufacture in a way, for example by bending metal sheets, which are then polished to a high gloss by Pormen of metals, glasses or plastics, which then have a high gloss be brought, or by casting, pressing or Milling of metal parts "

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Claims (1)

Patent claims 1. Reflector for radiant energy, characterized by a " composed of a number of elementary reflection surfaces • reflective surface that is connected to each other at their top and then merge with each other and at their lower edges lateral edges are separated from one another by steps * or vice versa, and by such an orientation of the tangent planes at each point of the individual elementary reflection surfaces, that the images of the light source on one to be illuminated Area (working area) according to a predetermined law superimpose or adjoin one another ■ " 2. Reflector according to claim 1, characterized in that additional reflective surfaces on the upper floor area of the Reflector are arranged in such a way that the incident thereon Radiant energy is directed at the work surface " 3 »reflector according to claim 1 or 2, characterized in that that further additional reflective surfaces are provided on upper bathing area of the reflector that in the same through breaks are provided and that the further additional Re * flexion surfaces are arranged so that the impinging Radiation falls through the breakthroughs. 009850/0724 ORIGSMAL IfSlSPECTED 16220U if, reflector according to requirement 1 to 3> characterized in that there are additional reflection surfaces below the steel sources are arranged in such a way that the incident radiation thrown onto other areas of the surface of the reflector will. 5. Reflector according to claim 1 to 4 »characterized in that that additional reflective surfaces are provided, the radiation on zones outside of the work surface to be illuminated direct ο "-...,