Vehicle interior illumination structure

Disclosed is a vehicle interior illumination structure comprising, in combination, an instrument panel 10 installed in a front interior area of a vehicle, and a light-guiding illumination member 2 disposed in the instrument panel. The instrument panel 10 is formed with a step portion S laterally extending at a height approximately equal to or above that of a mounting portion of a shaft of a steering wheel 35 to the instrument panel. The step portion S is defined in such a manner that a step upper surface 11f located on the upper side of the step portion and a step lower surface 12f located on the lower side of the step portion are formed in the instrument panel 10, and the step upper surface 11f has a rear edge 11p protruding in the rearward direction of the vehicle relative to a front edge 12p of the step lower surface 12f. The illumination member 2 is arranged to extend laterally at a position which is adjacent to the front edge 12p of the step lower surface 12f and capable of preventing illumination light of the illumination member 2 from directly coming within the field of view of a driver sitting in a front seat in the vehicle interior. The vehicle interior illumination structure of the present invention can prevent illumination light of the illumination member from obstructing the driver's view.

TECHNICAL FIELD

The present invention relates to a structure for illuminating the interior of a vehicle, such as an automobile, and more particularly to a vehicle interior illumination structure comprising, in combination, an instrument panel installed in a front interior area of a vehicle and a light-guiding illumination member disposed in the instrument panel.

BACKGROUND ART

Late years, with a view to providing sophisticated design of a vehicle interior and creating a tranquil atmosphere during illumination, various efforts have been made to adopt an indirect illumination technique to a system for illuminating the interior of a vehicle, such as an automobile, during the night etc., in place of a commonly used conventional technique, so-called “direct illumination”. Differently from the direct illumination technique designed to illuminate a target region by direct light from an illumination member capable of emitting illumination light, the indirect illumination technique is designed to reflect illumination light from an illumination member by a wall surface adjacent thereto and illuminate a target region using the reflected light. Thus, the indirect illumination technique can eliminate the disadvantage in the direct illumination technique, such as excessive brightness in the entire vehicle interior or in the illuminated region and the vicinity thereof, so as to create more tranquil/relaxed atmosphere.

As the system for illuminating the interior of a vehicle, such as an automobile, there has been known one type designed to incorporate an illumination member having a light-guiding performance (hereinafter referred to as “light-guiding illumination member”) in a vehicle interior component, and allow light of a light source provided inside or outside the illumination member to be emitted from the illumination member so as to illuminate the vehicle interior by the emitted light.

For example, the following Patent Publication 1 discloses an illumination member comprising a light guide plate incorporated inside a light-transparent panel, and a light source (e.g. light-emitting diode) disposed on the side of the light guide plate, wherein light from the light source enters from a side surface into the inside of the light guide plate and then exits from a front surface of the light guide plate.

The Patent Publication 1 (Japanese Patent Laid-Open Publication No. 2004-90897) discloses an illumination system for a vehicle, in which the above illumination member is disposed in a center console box, an interior ceiling above a rearview mirror, an instrument panel or a door panel.

Generally, an instrument panel installed in a front interior area of an automobile is provided with various components, such a glove box, and various manual operation elements, such as switches and a wind-direction adjusting lever for an air-conditioning system. Therefore, in dark circumstances, such as the nighttime, it is required to allow an occupant, such as a driver, to recognize the shape and position of the instrument panel so as to ensure usability or user-friendliness in using or manually operating such components and manual operation elements.

In the conventional illumination system where the illumination member is incorporated in an instrument panel to ensure the above user-friendliness, illumination light from the illumination member is liable to directly come within the field of view of a driver sitting in a front seat in a vehicle interior and obstruct the driver's view. The illumination light directly coming within the driver's field of view will cause difficulty in driving during the illumination at night etc., and induce an uncomfortable or disturbed feeling in the driver.

Even if an indirect illumination technique is simply applied to the illumination system associated with an instrument panel, illumination light from an illumination member is likely to directly come within the field of view of a driver sitting in a front seat in a vehicle interior and obstruct the driver's view, depending on the position of the illumination member and the direction of the illumination light.

SUMMARY OF THE INVENTION

In view of the above circumstances, it is a fundamental object of the present invention to provide a vehicle interior illumination structure comprising, in combination, an instrument panel installed in a front interior area of a vehicle, and a light-guiding illumination member disposed in the instrument panel, which is capable of preventing illumination light of the illumination member from directly coming within the field of view of a driver sitting in a front seat.

In order to achieve the above object, the present invention provides a vehicle interior illumination structure comprising, in combination, an instrument panel installed in a front interior area of a vehicle and located on the lower side of a front windshield glass, and a light-guiding illumination member disposed in the instrument panel, wherein the front interior area is defined by the front windshield glass and opposed side window glasses on the rearward side of the front windshield glass. In this vehicle interior illumination structure, the instrument panel is formed with a step portion extending laterally at a height approximately equal to or above that of a mounting portion of a steering wheel shaft to the instrument panel. The step portion is defined in such a manner that a step upper surface located on the upper side of the step portion and a step lower surface located on the lower side of the step portion are formed in the instrument panel, and the step upper surface has a rear edge protruding in the rearward direction of the vehicle relative to a front edge of the step lower surface. Further, the illumination member is arranged to extend laterally at a position which is adjacent to the front edge of the step lower surface and capable of preventing illumination light of the illumination member from directly coming within the field of view of a driver sitting in a front seat in the vehicle interior.

As used in the specification, the term “driver” means an occupant who has an average physique of American male adults and sits in a driver's seat in a seated posture conforming to a so-called “hip point” to be uniquely set to each vehicle.

As used in the specification, the term “lateral” or “laterally” means a width direction of the vehicle.

According to the vehicle interior illumination structure of the present invention, the instrument panel is formed with the step portion extending laterally to segment at least a part of the instrument panel into upper and lower portions, wherein the step upper surface or a surface of the upper portion is arranged to have a rear edge protruding in the rearward direction of the vehicle relative to a front edge of the step lower surface or a surface of the lower portion. Further, the illumination member extends laterally at a position adjacent to the front edge of the step lower surface. Thus, when it is necessary to illuminate the interior of a vehicle, for example, during driving through a tunnel or at night, illumination light from the illumination member can adequately illuminate the instrument panel so as to allow the driver to readily recognize the position of the instrument panel without excessively lightening the front exterior region.

In this case, the illumination light of the illumination member is emitted from an inner region of the step portion, and thereby the illumination effect is primarily induced by reflected light from the step lower surface and/or a folded region of the step upper surface. This makes it possible to achieve indirect illumination and thereby eliminate the disadvantage in direct illumination, such as excessive brightness in an illuminated region and the vicinity thereof so as to create more tranquil/relaxed atmosphere in the vehicle interior. In addition, the illumination member is arranged at a position capable of preventing illumination light of the illumination member from directly coming within the field of view of the driver sitting in the front seat in the vehicle interior. This makes it possible to more effectively prevent the illumination light from obstructing the driver's view. That is, an adverse affect on driving to be caused by illumination light getting into driver's eye can be more effectively avoided.

DETAILED DESCRIPTIONS OF THE INVENTION

With reference to the accompanying drawings, an embodiment of the present invention will now be described in detail.

FIG. 1is a schematic perspective view showing a front interior area of an automobile, which has a vehicle interior illumination structure according to a first embodiment of the present invention. As shown inFIG. 1, an instrument panel10is installed in the front interior area of the automobile to cover a lower region of the front interior area, and a front windshield glass20is disposed to extend upward from the vicinity of the front edge of the instrument panel10so as to cover an upper region of the front interior area. That is, the front edge of the instrument panel10is located adjacent to the lower edge of the front windshield glass20. A pair of side window glasses25are disposed, respectively, at laterally opposite outer ends of the front windshield glass20and on the rearward side of the front windshield glass20. A front or upper portion of the instrument panel10has opposite lateral edges located adjacent to lower edges of the corresponding side window glasses25.

The instrument panel10includes a center console unit16which extends from an approximately laterally central region thereof in a vertical and rearward direction of the vehicle. This center console unit16has a front inclined portion16fformed with a lever guide groove16gfor allowing a gearshift lever31to penetrate therethrough, as described in detail later with reference toFIG. 3. The center console unit16also includes a cup holder32on the lower and rearward side of the lever guide groove16g, and three manual setting dials41(41A,41B,41C: seeFIG. 3) for an air-conditioning system, on the upper and frontward side of the lever guide groove16g. Further, various types of manual operation buttons42(42A,42B,42C,42D: seeFIG. 3) for an audio system are disposed in a region of the instrument panel10on the upper side of the air-conditioning manual setting dials41, and two conditioned-air outlet ports43B,43C are formed in a region of the instrument panel10on the upper side of the manual operation buttons42.

A right zone of the instrument panel10relative to the center console unit16(when seeing from the rear to the front of the vehicle) is located in front of a driver's seat (not shown). Various meters, such as a vehicle speed meter44and an engine speed meter45, are arranged in a region of the instrument panel10facing a steering wheel35, and a conditioned-air outlet port43D is formed in a region of the instrument panel10on the right side of the meters. Further, various switches46, such as a fog lamp switch, are disposed in a region of the instrument panel10on the lower side of the conditioned-air outlet port43D.

A left zone of the instrument panel10relative to the center console unit16(when seeing from the rear to the front of the vehicle) is located in front of a front passenger seat (not shown), and formed with a glove box17serving as a small storage compartment. A conditioned-air outlet port43A is formed in a region of the instrument panel10on the upper left side of the glove box17. The instrument panel10also has a pair of cup holders36provided in a slidable manner, just below the conditioned-air outlet port43A located at the left end of the vehicle interior, and the conditioned-air outlet port43D located at the right end of the vehicle interior, respectively.

A pair of door mirrors23,24each serving as a side mirror for visually checking primarily the lateral rearward of the vehicle are provided, respectively, at the front ends of right and left front doors21,22.

In the following description, each of the air-conditioning manual setting dials41(41A,41B,41C), each of the audio manual operation buttons42(42A,42B,42C,42D) and each of the conditioned-air outlet ports43(43A,43B,43C,43D) will be occasionally described, respectively, as “air-conditioning manual setting dial(s)41”, “audio manual operation button(s)42” and “conditioned-air outlet port(s)43” simplistically by removing the alphabetical code, unless necessary to distinctively describe a specific one of them.

In the first embodiment, the instrument panel10preferably comprises an upper unit11constituting an upper portion thereof and a lower unit12constituting a lower portion thereof. While the center console unit16in this embodiment is assembled as a separate member into the instrument panel10, the inclined portion16fof the center console unit16in the assembled state belongs to the lower unit12of the instrument panel10. It is understood that the center console unit16may be integrally formed with the lower unit12of the instrument panel10.

The instrument panel10has a step portion S formed along the boundary between the upper unit11and the lower unit12. That is, the step portion S extends laterally to segment the instrument panel10into upper and lower portions. An illumination member2having a light-guiding performance (hereinafter referred to as “light-guiding illumination member”) is disposed in the step portion S. Preferably, the step portion S and the illumination member2are provided to extend over the entire width of the instrument panel10while getting around a mounting portion of a shaft of the steering wheel35. The step portion S is formed at a height approximately equal to or above that of the mounting portion of the shaft of the steering wheel35to the instrument panel10to create a sophisticated luxury design. In particular, the step portion S may be located above a specific position adjacent to the lower edge of the laterally right, left or central conditioned-air outlet port (a specific position below the lower edge by a given distance (e.g. 20 cm)) to provide more enhanced design.

The step portion S and the illumination member2will be described in more detail below.

FIG. 2is a perspective view showing the fundamental structure of the step portion S of the instrument panel10, andFIGS. 3 and 4are perspective views showing the structure of the step portion S on the upper side of the center console unit16and the structure of the step portion S on the upper side of the glove box, respectively.

As shown inFIG. 2, the instrument panel10has a surface11fof the upper unit11located on the upper side of the step portion S (step upper surface11f), and a surface12fof the lower unit12located on the lower side of the step portion S (step lower surface12f). The step upper surface11fis folded obliquely downward in the frontward direction of the vehicle to form a folded region11b, and the front edge of the folded region11b(or the lower edge of the step upper surface11f) is engaged with the front edge of the step lower surface12f(or the upper edge of the step lower surface12f) to define the step portion S. That is, the step upper surface11fhas a rear edge11pprotruding in the rearward direction of the vehicle relative to the front edge12pof the step lower surface12f.

The illumination member2is disposed in the innermost region of the step portion S or in the vicinity of the front edge12pof the step lower surface12f, to extend laterally. As schematically shown inFIG. 6, the illumination member2is made of a material having a light-guiding performance, such as acrylic resin or polycarbonate resin, and formed in an elongated rod or column shape. A light source4(e.g. a light-emitting diode, a halogen lamp or an incandescent lamp) is disposed at one lateral end of the illumination member2. The light source4is designed to be supplied with an electric power in conjunction with the activation of side or head lamps (not shown) of the vehicle. The above material has flexibility (resiliency), and thereby the illumination member2can be set along a curved region having a certain curvature without any problem.

In a conventional manner, light from the light source4enters from one end surface to the inside of the illumination member2, and exits from a front surface of the illumination member2to illuminate the surrounding.

Instead of providing the separate light source2as above, a line-shaped or dot-shaped light source may be disposed within the illumination member to illuminate the surrounding.

As shown inFIG. 5, a groove portion11ghaving an approximatelyshape in section and an opening on the lower side thereof is formed adjacent to the front edge of folded region11bof the upper unit11to extend laterally, and the illumination member2is contained in the groove portion11g. The opening of the groove portion11gcontaining the illumination member2is located to face the step lower surface12f, and closed by a cover member13made of transparent or semi-translucent light-transmittable glass or resin to protect the illumination member2contained therein.

As above, the groove portion11gcontaining the illumination member2has the opening facing the step lower surface12f. Thus, light emitted from the front surface of the illumination member2transmits through the cover member13as indicated by the one-dot-chain-line arrows inFIG. 5and falls on the step lower surface12f. Then, resulting reflected light is used for illumination. That is, the step lower surface12fis illuminated by means of the so-called indirect illumination.

Thus, when it is necessary to illuminate the vehicle interior, for example, during driving through a tunnel or at night, the instrument panel10can be illuminated by illumination light from the illumination member2, so as to allow a driver to recognize the position of the instrument panel10without excessively illuminating the front interior area of the vehicle.

In this case, when a driver sitting in a front seat (driver's seat) (not shown), particularly at a position generally considered to be advantageous to facilitating driving, visually recognizes the above illuminated region in this sitting posture, the illumination member2is intercepted or blocked by the step upper surface11f, and thereby the illumination member2itself never comes within the driver's field of view, as seen in the driver's line of sight indicated by the two-dot-chain-line arrow “e” inFIG. 5. In addition, the step upper surface11fcan logically prevent the illumination member2from being reflected on the front windshield glass20and the side wind glasses25to eliminate adverse affects on occupant's driving. Each dimension and the positional relationship of the elements of the vehicle interior illumination structure are arranged such that illumination light directly emitted from the illumination member2is almost blocked by the step upper surface11fto substantially prevent the illumination light from directly coming within the driver's field of view. WhileFIG. 5shows the step portion S in a region of the instrument panel20in front of the front passenger seat, the step portion S adjacent to the center console unit16is designed in the same manner as that described above.

In the vehicle interior illumination structure according to the first embodiment, the illumination is performed by means of indirect illumination. This makes it possible to eliminate the disadvantage in direct illumination, such as excessive brightness in an illuminated region and the vicinity thereof, so as to create more tranquil/relaxed atmosphere in the vehicle interior. In addition, the vehicle interior illumination structure is designed to prevent illumination light of the illumination member2from directly coming within the field of view of a driver sitting in the front seat in the vehicle interior, and prevent an image of the illumination member2from coming within the driver's field of view through the front windshield glass20and the side wind glasses25. This makes it possible to more reliably prevent the illumination light from obstructing the view of the driver sitting in the front seat. That is, the vehicle interior illumination structure can more reliably suppress an adverse affect on driving to be caused by illumination light getting into driver's eye, and can reduce an uncomfortable or disturbed feeling during driving in situations requiring to illuminate the vehicle interior, such as driving through a tunnel or at night.

Further, the illumination member2for the above indirect illumination is provided to extend over the approximately entire width of the instrument panel10. Thus, during illumination at night or the like, the vehicle interior illumination structure can give an impression as if a region of the instrument panel10on the upper side of the illuminated region is almost entirely floating to provide enhanced interior design and create a sophisticated luxury atmosphere.

While the step portion S and the illumination member2in the first embodiment are provided to extend over the approximately entire width of the instrument panel10, the step portion S and the illumination member2may be provided only in a specific lateral range of the instrument panel10according to need.

Further, while the vehicle interior illumination structure according to the first embodiment is designed to reflect illumination light from the illumination member2disposed at the inner region of the step portion S, by the step lower surface12f, it may be designed to reflect the illumination light by the folded region11bof the step upper surface11f, in place of or in addition to the step lower surface12f.

In the first embodiment, the upper unit11of the instrument panel10including the step upper surface11fhas a relatively dark tone, such as black, gray, dark blue, brown or a color tone based thereon. Preferably, the lower unit12including the step lower surface12falso has a relatively dark tone.

As above, at least the upper unit11of the instrument panel10has the relatively dark tone. This makes it possible to prevent the upper unit11itself of the instrument panel11including the step upper surface11ffrom being reflected on the front windshield glass20, for example, even during driving through a tunnel or at night, and keep the reflection from obstructing the driver's view.

However, if the upper unit11of the instrument panel10, particularly the step upper surface11f, has the dark tone, and a manual operation element, such as the manual operation buttons42(42A to42D) for an audio system as shown inFIG. 3, is arranged on the step upper surface11fwithout any measures, a driver is likely to misjudge a distance to the step upper surface11fwhen operating the manual operation button42due to indistinctness in a region of the step upper surface11fadjacent to the step portion S, and cause driver's discomfort, for example, due to a finger sprain or finger-sprain-like accident.

This undesirable phenomenon becomes increasingly prominent when the step upper surface11fand the step lower surface12fhave inclined zones11h,12h, respectively, in the vicinity of the step portion S (seeFIG. 5), and each of the inclined zones11h,12hhas a different angle of inclination, particularly the step upper surface11fis inclined closer to a vertical line than the step lower surface12f. This condition makes it difficult for the driver to recognize a distance to the region of the step upper surface11fadjacent to the step portion S.

From this point of view, in the first embodiment, in order to increase the degree of visibility of the manual operation buttons42(42A to42D) disposed on the step upper surface11f, against a background of the step upper surface11fhaving the relatively dark tone, each logo (RADIO, CD, TAPE, MD) of the manual operation buttons42(42A to42D) is designed to emit light therefrom, or is made of a luminescent material, as shown inFIG. 3. Instead of such a logo, a symbol mark may be attached to each of the manual operation buttons42, and may be designed to emit light therefrom, or made of a luminescent material. Alternatively, each of the manual operation buttons42(42A to42D) themselves may be designed to emit light therefrom, or covered by a luminescent material. Further, instead of emitting light or using a luminescent material, the logos, symbol marks or buttons may be colored by a lighter and more visible color than that of the step upper surface (e.g. red, white or yellow).

As above, the manual operation element (manual operation button42) disposed on the step upper surface11fhas a higher degree of visibility that that of the step upper surface11f. Thus, even though the upper unit11of the instrument panel10including the step upper surface11fhas the relatively dark tone, the manual operation buttons42(42A to42D) can be visually recognized without any the problem to effectively avoid driver's discomfort, for example, due to a finger-sprain-like accident.

As mentioned above, particularly when the step upper surface11fand the step lower surface12fhave the inclined zones11h,12h, respectively, in the vicinity of the step portion S (seeFIG. 5), and each of the inclined zones11h,12hhas a different angle of inclination, the driver has difficulty in recognizing a distance to the region of the step upper surface11fadjacent to the step portion S. Even in this condition, the above manual operation buttons42can prevent the above problem from occurring.

In addition to the audio manual operation buttons42, the manual operation element to be increased in the degree of visibility may include a wind-direction adjusting lever (not shown) provided at an opening portion of each of the conditioned-air outlet ports43formed in the step upper surface11for in the vicinity of the opening portion, and a slidable portion of each of the right and left cup holders36provided in the step upper surface11f.

In the first embodiment, when the lower unit12of the instrument panel10also has a relatively dark tone, a manual operation element disposed on the step lower surface12fof the lower unit12, for example, the air-conditioning manual setting dials41, a manual operation lever18aof a lid portion18of the glove box17may be designed to increase the degree of visibility in the above manner so as to achieve the same effect as that in the manual operation element provided in the step upper surface11f.

When the degree of visibility is increased in the manual operation elements disposed on both the step upper surface11fand the step lower surface12f, it is preferable that the manual operation element on the step upper surface11fhas a lower degree of visibility than that of the manual operation element on the step lower surface12f.

While the manual operation element on the step upper surface11fis liable to be reflected on the front windshield glass20because the step upper surface11fis located closer to the front windshield glass20and more frontward than the step lower surface12f, the above arrangement can suppress the reflection onto the front windshield glass20.

It is also effective in increasing the degree of visibility in the step upper surface11fto provide a given ornament on a region of the step upper surface11fof the instrument panel10adjacent to the step portion S. In the first embodiment, as such an ornament, a line-shaped decorative sheet30having a relatively striking or distinctive color is attached on the vicinity of the rear edge11pof the step upper surface11f. This makes it easy to recognize the position of the step portion S so as to more effectively prevent the occurrence of the aforementioned problem, such as a finger-sprain-like accident.

Any other suitable type of ornament, such as a line-shaped label, may be provided on the region adjacent to the step portion S.

If the illumination member2disposed in the step portion S on the upper side of the lid portion18of the glove box located in opposed relation to the front passenger seat (not shown) is designed to perform direct illumination, and a driver visually checks the door mirror23on the outer side of the front passenger seat, a region illuminated by the illumination member2is more likely to get into driver's eye than the door mirror23. In contrast, the vehicle interior illumination structure according to the first embodiment is designed to allow the illumination member2to perform indirect illumination, or to prevent illumination light of the illumination member2from directly coming within the field of view of the driver sitting in the front seat, so as to more effectively keep the illumination light from obstructing the driver's view. That is, an adverse affect on driving to be caused by illumination light getting into driver's eye when the driver visually checks the door mirror23can be more effectively avoided. While the above description has been made in connection with the left door mirror23, the same effects can also be obtained when the driver visually checks the right door mirror24adjacent to the driver's seat.

All of the manual operation elements may be disposed only on the step lower surface12fwithout arranging the manual operation buttons42(42A,42B,42C,42D) etc., on the upper side of the center console unit. In this case, all of the manual operation elements can be illuminated by the illumination member2, to effectively prevent the occurrence of a finger-sprain-like accident when the driver operates the manual operation buttons or the like.

In the first embodiment, the inclined portion16fon the front side of the center console unit16is located below the step portion S, or corresponds to the step lower surface12fin the central region of the instrument panel10. As mentioned above, the air-conditioning manual setting dials41(41A,41B,41C) are disposed on the front upper region of the inclined portion16f(or in the vicinity of the step portion S). The angle of inclination of the inclined portion16fis set to be approximately equal to that of the inclined zone12h(seeFIG. 5). These air-conditioning manual setting dials41are illuminated by the illumination member2disposed in the step portion S adjacent to the front edge of the step lower surface (inclined portion)16f.

Each of the manual setting dials41is formed in a circular disc shape having a given thickness (or in a cylindrical column shape having a given height) as particularly shown inFIG. 3, and the manual setting dial itself protrudes from the inclined portion16ftoward the vehicle interior by a given height, as seen inFIG. 5. Each height of the dials41protruding from the inclined portion16f, and each detention, shape and the positional relation of other elements of the vehicle interior illumination structure are arranged to allow the setting dials41(41A,41B,41C) to be hidden by the step upper surface11fwhen the driver sitting in the front seat visually recognizes the inclined portion16fon the front side of the center console unit16, the step portion S and the step upper surface11fwhich are reflected on the front windshield glass20. That is, the vehicle interior illumination structure is designed to allow the setting dials41(41A,41B,41C) to be hidden by the step upper surface11f, with respect to the driver's line e′ of sight reflected by the front windshield glass20(seeFIG. 5).

Thus, the vehicle interior illumination structure is designed to prevent the setting dials41(41A,41B,41C), particularly the upper side-wall surfaces thereof illuminated by the illumination member2from being reflected on the front windshield glass20distinctively in a light tone, for example, even during driving through a tunnel or at night, and keep the reflection from obstructing the driver's view.

Preferably, the setting dials41(41A,41B,41C) in this embodiment have a lighter tone than that of the step upper surface11f, for example, a metallic color. This allows the setting dials41to stand out against the indirect illumination by the illumination member2so as to ensure sufficiently high visibility. This arrangement may also be applied to the switches46.

As mentioned above, a left region of the instrument panel10relative to the center console unit16is formed with the glove box17serving as a small storage compartment. As particularly shown inFIGS. 4 and 7, the glove box17comprises a pocket17alocated below the step portion S of the instrument panel10and concavedly curved in the frontward direction of the vehicle, and a lid portion18for covering the pocket17ain an openable and closable manner.

Specifically, the glove box17is covered by the lid portion18serving as a rear wall thereof, and the lid portion18can be swingably moved to rotate the pocket17aabout the vicinity of the lower edge of the glove box17, so that the pocket17ais opened rearward in its entirety. The lid portion18has a manual operation lever18afor allowing the lid portion18to be released from its closed state.

The pocket17ais located at a position allowing an inner space of the pocket17ato be illuminated by illumination light from the illumination member2disposed adjacent to the front edge of the step lower surface12f.

Thus, illumination light from the illumination member2can be effectively used for illuminating the entire inner space of the pocket17aof the glove box17to thereby achieve enhanced user-friendliness in opening the lid portion18of the glove box17to use the pocket17a, without providing an additional illumination member.

Further, a detection switch19is disposed in the vicinity of an opening of the pocket17ato detect whether the lid portion18is in an open position or in a closed position, and an intensity of illumination light from the illumination member2is adjusted according to a detection signal of the detection switch19. Specifically, the vehicle interior illumination structure is designed to increase an intensity of illumination light from the illumination member2in the open position of the lid portion18as compared to that in the closed position of the lid portion18.

For example, the illumination intensity may be adjusted by controlling an emission intensity of the light source4. Preferably, the illumination member2to be disposed in a region of the instrument panel10corresponding to the glove box17is provided independently of the illumination member2to be disposed in the remaining region of the instrument panel10.

As above, the vehicle interior illumination structure according to the first embodiment is designed to increase an intensity of illumination light from the illumination member2in the open position of the lid portion18for covering the pocket17ain an openable and closable manner, as compared to that in the closed position of the lid portion18. Thus, when the lid portion18is in the open position where it is necessary to illuminate the inner space of the pocket17a, the inner space can be more sufficiently illuminated. When the lid portion18is in the closed position where it is unnecessary to illuminate the inner space of the pocket17a, the illumination light is adjusted to have a relatively low intensity so as to more effectively prevent the illumination light from obstructing the view of the driver sitting in the front seat. That is, an adverse affect on driving to be caused by illumination light getting into driver's eye can be more effectively avoided.

If the illumination member2disposed in the step portion S on the upper side of the lid portion18of the glove box located in opposed relation to the front passenger seat (not shown) is designed to perform direct illumination, and a driver visually checks the door mirror23on the outer side of the front passenger seat, a region illuminated by the illumination member2is more likely to get into driver's eye than the door mirror23. In contrast, the vehicle interior illumination structure according to the first embodiment is designed to allow the illumination member2to perform indirect illumination, or to prevent illumination light of the illumination member2from directly coming within the field of view of the driver sitting in the front seat, so as to more effectively keep the illumination light from obstructing the driver's view. That is, an adverse affect on driving to be caused by illumination light getting into driver's eye can be more effectively avoided. While the above description has been made in connection with the left door mirror23, the same effects can also be obtained when the driver visually checks the right door mirror24adjacent to the driver's seat.

While the glove box17in the first embodiment is disposed below the step portion S of the instrument panel10, such a glove box may be disposed above the step portion of the instrument panel.

A vehicle interior illumination structure according to a second embodiment of the present invention will be described below. In the following description, the same element or component as that in the first embodiment is defined by the same reference numeral or code, and its further description will be omitted.

As shown inFIG. 8, in the second embodiment, an instrument panel10is formed with a pocket51located above a step portion S thereof and concavedly curved in the frontward direction of a vehicle. A lid portion55is provided to cover the pocket51in an openable and closable manner so as to form a glove box50above the step portion S.

The pocket51is composed of a separate member56(pocket member), for example, made of synthetic resin and formed in an approximatelyshape in section, and integrally joined to an step upper surface11fof the instrument panel10at an upper edge and opposed right and left lateral edges thereof.

A groove portion53is formed below an opening of the pocket51to extend laterally, and an illumination member2is contained in the groove portion53. The groove portion53has an approximately rectangular-shaped periphery in section, and the periphery has a top wall53aand a bottom wall53bwhich are made of transparent or semi-translucent light-transmittable glass or resin. Each dimension, shape and the positional relationship of the elements of the vehicle interior illumination structure are arranged to allow the top wall53aof the groove portion53to face an inner space of the pocket51and allow the bottom wall53bof the groove portion53to face a region of the step lower surface12fadjacent to the step portion S.

As above, the groove portion53containing the illumination member2has the light-transmittable bottom wall53blocated to face the step lower surface12f. Thus, light emitted from the front surface of the illumination member2transmits through the bottom wall53band falls on the step lower surface12f. Then, resulting reflected light is used for illumination. That is, a region of the instrument panel10on the lower side of the glove box50is illuminated by means of the so-called indirect illumination.

The groove portion53also has the light-transmittable top wall53alocated to face the inner space of the pocket51. Thus, light emitted from the front surface of the illumination member2transmits through the top wall53aand illuminates the inner space of the pocket51.

Thus, illumination light from the illumination member2can be effectively used for illuminating the inner space of the pocket51of the glove box50to provide enhanced user-friendliness in opening the lid portion55of the glove box50to use the pocket51, without providing an additional illumination member.

The above effect can also be obtained even if the pocket51is always opened without the lid portion55. Specifically, as long as the region on the lower side of the glove box52is illuminated by illumination light from the illumination member2, a driver can readily recognize the position of the glove box50without illuminating the entire vehicle interior, for example, even during driving in situations requiring to illuminate the vehicle interior, such as driving through a tunnel or at night.

Further, as with the first embodiment illustrated inFIGS. 4 and 7, a detection switch for detecting whether the lid portion55is in an open or closed position may be provided in the vehicle interior illumination structure according to the second embodiment, and an intensity of illumination light from the illumination member2may be adjusted according to a detection signal of the detection switch. Specifically, the vehicle interior illumination structure is designed to increase an intensity of illumination light from the illumination member2in the open position of the lid portion55as compared to that in the closed position of the lid portion55, so as to obtain the same effect as that in the first embodiment.

With reference toFIG. 9, a vehicle interior illumination structure according to a third embodiment of the present invention will be described below. In the following description, structurally and functionally the same element or component as that in the first embodiment illustrated inFIGS. 1 to 7is defined by the same reference numeral or code, and its further description will be omitted.

FIG. 9is a schematic perspective view showing a front interior area of an automobile, which has a vehicle interior illumination structure according to the third embodiment of the present invention. As shown inFIG. 9, an instrument panel60covering a lower region of the front interior area comprises an upper unit61having a rear region formed to expand obliquely downward in the rearward direction of the vehicle, and a lower unit62having a front edge formed to extend approximately along a rear edge of the upper unit61. As with the first embodiment, a step portion S is formed along the boundary between the rear edge of the upper unit61and the front edge of the lower unit62to extend laterally so as to segment the instrument panel10into upper and lower portions.

A light-guiding illumination member52is disposed in the step portion S. Preferably, the step portion S and the illumination member52are provided to extend over the entire width of the instrument panel60while getting around a mounting portion of a shaft of a steering wheel35.

The instrument panel60includes a center console unit66which extends from an approximately laterally central region thereof in a vertical and rearward direction of the vehicle. The center console unit66has a front upper region formed as an inclined portion provided with a gearshift lever31. In the third embodiment, a plurality of manual setting dials91for an air-conditioning system are disposed on a rear side of the central region of the upper unit61of the instrument panel60. Further, various types of manual operation buttons92and a display panel99for an audio system are disposed in a region of the instrument panel60on the front upper side of the manual setting dials91.

Two conditioned-air outlet ports93B,93C are formed, respectively, on right and left sides of the display panel99. Two conditioned-air outlet ports93A,93D are formed, respectively, in the vicinities of right and left ends of the upper unit61of the instrument panel60. Various switches46, such as a fog lamp switch, are disposed in a region of the instrument panel60on the lower side of the right conditioned-air outlet port93D.

As with the first embodiment, the step portion S in the third embodiment is formed at a height approximately equal to or above that of the mounting portion of the shaft of the steering wheel35to the instrument panel60. In particular, the step portion S is located above a specific position adjacent to the lower edge of the laterally right, left or central conditioned-air outlet port (a specific position below the lower edge by a given distance (e.g. 20 cm)) to provide more enhanced design.

As with the first embodiment, a front windshield glass20is disposed to extend upward from the vicinity of the front edge of the instrument panel60so as to cover an upper region of the front interior area. That is, the front edge of the instrument panel60is located adjacent to the lower edge of the front windshield glass20. A pair of side window glasses25are disposed, respectively, at laterally opposite outer ends of the front windshield glass20and on the rearward side of the front windshield glass20. A pair of door mirrors23,24each serving as a side mirror for visually checking primarily the lateral rearward of the vehicle are provided, respectively, at the front ends of right and left front doors21,22. When a driver visually checks each of the door mirrors23,24under the condition that the front doors21,22are closed, he/she will view the door mirror through the side window glass25.

The illumination member52disposed in the step portion S will be described in more detail below.

As mentioned above, the instrument panel60in the third embodiment comprises the upper unit61having the rear region formed to expand obliquely downward in the rearward direction of the vehicle, and the lower unit62having the front edge formed to extend approximately along the rear edge of the upper unit61. The step portion S is formed along the boundary between the rear edge of the upper unit61and the front edge of the lower unit62, in the same manner as that in the first embodiment. Thus, the illumination member52disposed in the step portion S extends to form a curved line having a laterally central portion which protrudes rearward relative to a laterally outer portion thereof. When this illumination member52is set in the step portion S, it may be divided into right and left portions, for example, on the basis of the laterally central portion. In this case, each of the right and left illumination members has an independent light source.

In the third embodiment, a light source54is disposed at an approximately laterally central portion of the illumination member52. Thus, a luminance of light emitted from the light source54and guided through the inside of the illumination member52becomes lower as a distance from the light source is increased. That is, the illumination member52has a laterally outward portion with a lower luminance than that of a laterally inward portion thereof.

This makes it possible to effectively avoid an adverse affect on driving to be caused by illumination light from the laterally outward portion which obstructs the driver's view as compared to that from the laterally inward portion. According to the third embodiment, this effect can be obtained in a simplified structure where the light source54of the illumination member54is simply disposed at a laterally inward position.

As another means for allowing the illumination member52to have a laterally outward portion with a lower luminance than that of a laterally inward portion thereof, a glass or resin cover member covering the lower side of the illumination member52(see the cover member13inFIG. 5) may be designed to have a laterally outward portion with a lower light transmittance than that of a laterally inward portion thereof.

This means for arranging the luminance of the illumination member52may be effectively applied to the first and second embodiments.

In the third embodiment, when an occupant visually checks the door mirror23or24disposed at the side of a vehicle body on the laterally outer side relative to the instrument panel60, a reflected image (virtual image) K1or K2of a region of the instrument panel60illuminated by the illumination member52is formed on the laterally right or left side window glass25in such a manner that at least a part of the reflected image overlaps the side mirror23or24. Even in that case, the illumination member52designed to perform indirect illumination and have a laterally outward portion with a lower luminance (intensity) than that of a laterally inward portion thereof can effectively prevent the occurrence of the problem that the reflected image K1or K2of the target region illuminated by the illumination member52distinctively stands out more than the door mirror23or24when the occupant visually checks the door mirror23or24, to obstruct the driver's view toward the side mirror23or24.

As shown inFIGS. 10 and 11, respective projections52a′,52b′,23′ of the lateral center52aand laterally outer edge52bof the illumination member52and the side mirror23which are viewed by a driver are located approximately on a straight line in a plane Fp orthogonal to the line Le of sight of the driver viewing the laterally outer edge52bof the illumination member52. Thus, when the driver visually checks the side mirror23on the outer side of the front passenger seat, he/she can more reliably view the side mirror23on an extension line of a region of the instrument panel indirectly illuminated by the illumination member52(i.e. inFIG. 9, the driver can move his/her line of sight from the lateral center52atoward the outer edge52bof the illumination member52to visually find the door mirror23on an extension line of the outer edge52b). This makes it possible to facilitate checking the position of the side mirror23.

While the illumination member in the first to third embodiments has been disposed in both the laterally right and left regions of the instrument panel, it may be disposed only in either one of the right and left regions. In this case, only the left illumination member located in opposed relation to the front passenger seat may be designed to have a luminance to be lowered in the laterally outward direction. Further, the central region of the instrument panel to be provided with a manual operation panel for an audio system may be designed to have no illumination member.

As mentioned above, the vehicle interior illumination structure of the present invention which comprises, in combination, the instrument panel installed in a front interior area of a vehicle and the light-guiding illumination member disposed in the instrument panel, makes it possible to prevent illumination light of the illumination member from obstructing the view of a driver sitting in a front seat, and prevent an upper region of the instrument panel itself or a manual operation element of an equipment disposed on the instrument panel from being reflected on a front windshield glass or side window glasses. The present invention can be effectively applied to an interior illumination system for a vehicle, such as an automobile.

In summary, the present invention provides a vehicle interior illumination structure comprising, in combination, an instrument panel installed in a front interior area of a vehicle and located on the lower side of a front windshield glass, and a light-guiding illumination member disposed in the instrument panel, wherein the front interior area is defined by the front windshield glass and opposed side window glasses on the rearward side of the front windshield glass. In this vehicle interior illumination structure, the instrument panel is formed with a step portion extending laterally at a height approximately equal to or above that of a mounting portion of a steering wheel shaft to the instrument panel. The step portion is defined in such a manner that a step upper surface located on the upper side of the step portion and a step lower surface located on the lower side of the step portion are formed in the instrument panel, and the step upper surface has a rear edge protruding in the rearward direction of the vehicle relative to a front edge of the step lower surface. Further, the illumination member is arranged to extend laterally at a position which is adjacent to the front edge of the step lower surface and capable of preventing illumination light of the illumination member from directly coming within the field of view of a driver sitting in a front seat in the vehicle interior.

As used in the specification, the term “driver” means an occupant who has an average physique of American male adults and sits in a driver's seat in a seated posture conforming to a so-called “hip point” to be uniquely set to each vehicle.

As used in the specification, the term “lateral” or “laterally” means a width direction of the vehicle.

According to the vehicle interior illumination structure of the present invention, the instrument panel is formed with the step portion extending laterally to segment at least a part of the instrument panel into upper and lower portions, wherein the step upper surface or a surface of the upper portion is arranged to have a rear edge protruding in the rearward direction of the vehicle relative to a front edge of the step lower surface or a surface of the lower portion. Further, the illumination member extends laterally at a position adjacent to the front edge of the step lower surface. Thus, when it is necessary to illuminate the interior of a vehicle, for example, during driving through a tunnel or at night, illumination light from the illumination member can adequately illuminate the instrument panel so as to allow the driver to readily recognize the position of the instrument panel without excessively lightening the front exterior region.

In this case, the illumination light of the illumination member is emitted from an inner region of the step portion, and thereby the illumination effect is primarily induced by reflected light from the step lower surface and/or a folded region of the step upper surface. This makes it possible to achieve indirect illumination and thereby eliminate the disadvantage in direct illumination, such as excessive brightness in an illuminated region and the vicinity thereof so as to create more tranquil/relaxed atmosphere in the vehicle interior. In addition, the illumination member is arranged at a position capable of preventing illumination light of the illumination member from directly coming within the field of view of the driver sitting in the front seat in the vehicle interior. This makes it possible to more effectively prevent the illumination light from obstructing the driver's view. That is, an adverse affect on driving to be caused by illumination light getting into driver's eye can be more effectively avoided.

In the vehicle interior illumination structure of the present invention, at least the step upper surface of the instrument panel may have a relatively dark tone. In this case, when the step upper surface is provided with a manual operation element, the manual operation element may have a higher degree of visibility than that of the step upper surface.

The “relatively dark tone” may include black, gray, dark blue, brown and a color tone based thereon. The “manual operation element” may include a switch, button or dial for an audio system, an air-conditioning system or an interior/exterior component/device, such as a fog lamp, and a wind-direction adjusting lever for the air-conditioning system. In order to increase the degree of visibility in the manual operation element, the manual operation element itself or its symbol mark or logo may be designed to emit light therefrom or made of a luminescent material, or may be colored, or may be increased in size.

According to this specific arrangement, at least the step upper surface of the instrument panel has a relatively dark tone. This makes it possible to prevent at least the step upper surface itself of the instrument panel from being reflected on the front windshield glass or side window glass distinctly in a light tone, for example, even during driving through a tunnel or at night, and keep the reflection from obstructing the driver's view.

In addition, the manual operation element provided on the step upper surface has a higher degree of visibility than that of the step upper surface. Thus, even though at least the step upper surface of the instrument panel has a relatively dark tone, any trouble in visually recognizing the manual operation element can be avoided. In particular, if the step upper surface of the instrument panel has a relatively dark tone to suppress the reflection of the instrument panel onto the front windshield glass or side window glass, and the vicinity of the step portion is indirectly illuminated in the above way without any measures, the driver is likely to misjudge a distance to the step upper surface when operating the manual operation element in dark circumstances, such as the nighttime, and cause driver's discomfort, for example, due to a finger-sprain-like accident. In this regard, the above manual operation element having a higher degree of visibility can prevent the occurrence of such a problem.

In the above vehicle interior illumination structure, when the step lower surface is also provided with a second manual operation element different from the first manual operation element on the step upper surface, the first manual operation element may have a lower degree of visibility than that of the second manual operation element.

According to this specific arrangement, the first manual operation element on the step upper surface has a lower degree of visibility than that of the second manual operation element on the step lower surface. Thus, while the first manual operation element on the step upper surface is liable to be reflected on the front windshield glass or side window glass as compared to the second manual operation element on the step lower surface, because the step upper surface is located closer to the front windshield glass or side window glass than the step lower surface, the reflection onto the front windshield glass or side window glass can be suppressed while avoiding the aforementioned driver's discomfort about the first manual operation element on the step upper surface.

In the vehicle interior illumination structure of the present invention, when at least the step upper surface of the instrument panel has a given dark tone, the illumination member may be designed to emit illumination light toward the step lower surface, and only the step lower surface may be provided with a manual operation element, in the vicinity of the step portion of the instrument panel.

A specific example of the “given dark tone” and the “manual operation element” may be the same as that described in connection with the aforementioned “relatively dark tone” and “manual operation element”.

According to this specific arrangement, the illumination member is designed to emit illumination light toward the step lower surface, and only the step lower surface is provided with a manual operation element in the vicinity of the step portion of the instrument panel. Thus, even though the step upper surface of the instrument panel has a relatively dark tone to suppress the reflection of the step upper surface onto the front windshield glass or side window glass, the manual operation element can be illuminated by the illumination light from the illumination member, so as to allow the driver to recognize the manual operation element without any problem.

In the vehicle interior illumination structure of the present invention, when at least the step upper surface of the instrument panel has a given dark tone, and the step upper surface is provided with a manual operation element, a region of the step upper surface adjacent to the step portion may have a given ornament to allow the adjacent region to have a higher degree of visibility than that of the remaining region of the step upper surface.

A specific example of the “given dark tone” and the “manual operation element” may be the same as that described in connection with the aforementioned “relatively dark tone” and “manual operation element”. The “given ornament” (provided on the region adjacent to the step portion) may include a line-shaped decorative sheet or label attached on the adjacent region.

According to this specific arrangement, even though the step upper surface of the instrument panel has a relatively dark tone to suppress the reflection of the step upper surface onto the front windshield glass or side window glass, the given ornament provided on the region of the step upper surface adjacent to the step portion allows the adjacent region to have an increased degree of visibility. Thus, the driver can recognize the step upper surface without any problem. In particular, if the step upper surface of the instrument panel has a relatively dark tone, and the vicinity of the step portion is indirectly illuminated in the above way without any measures, the driver is likely to misjudge a distance to the step upper surface when operating the manual operation element, and cause driver's discomfort, for example, due to a finger-sprain-like accident. In this regard, the given ornament provided on the region of the step upper surface adjacent to the step portion can increase the visibility of the manual operation element to prevent the occurrence of such a problem.

In the above vehicle interior illumination structure having the manual operation element with a higher degree of visibility than that of the step upper surface, or the given ornament provided on the region of the step upper surface adjacent to the step portion, the step upper and lower surfaces may have inclined zones, respectively, in the vicinity of the step portion. Each of the inclined zones may have an upper region located on the front side relative to a lower region thereof, and a different angle of inclination.

Generally, if each of the inclined zones of the step upper and lower surfaces has a different angle of inclination, the driver is apt to have difficulty in recognizing a distance to the step upper portion. Even in this case, the manual operation element with a higher degree of visibility or the given ornament can suppress the occurrence of a problem about driver's discomfort, for example, due to a finger-sprain-like accident.

In the vehicle interior illumination structure of the present invention, the illumination member may be disposed in a portion of the instrument panel located in opposed relation to a front passenger seat, and the vehicle may have a side mirror disposed at the side of a vehicle body on the laterally outer side relative to the instrument panel.

Even through the side mirror is disposed at the side of the vehicle body on the outer side of the front passenger seat, the illumination member arranged at a position capable of preventing illumination light of the illumination member from directly coming within the field of view of the driver sitting in the front seat in the vehicle interior makes it possible to more effectively prevent the illumination light from obstructing the driver's view when the driver visually checks the side mirror. Specifically, if the side mirror is disposed at the side of the vehicle body on the outer side of the front passenger seat, and the illumination member is designed to directly illuminate a target region of the instrument panel, the target region illuminated by the illumination member will distinctively stand out more than the side mirror when the driver visually checks the side mirror, resulting in insufficient backward checking using the side mirror. In contrast, the vehicle interior illumination structure performing indirect illumination as in the present invention can prevent illumination light from directly coming within the driver's field of view, and thereby an adverse affect on driving to be caused by illumination light obstructing the driver's view can be more effectively avoided.

In the vehicle interior illumination structure of the present invention, the instrument panel may be provided with an equipment element disposed adjacent to the step portion. The equipment element may be designed to be illuminated by the illumination member.

As used in the specification, the term “equipment element” means a concept encompassing the aforementioned “manual operation element”, and may include: an indicator or display and a manual operation member (buttons, dials, switches, etc.) for an audio system, an air-conditioning system or an in-vehicle electric or electronic component; and vehicle equipment, such as a cup holder, a change box and a glove box which are provided in or integrated with the instrument panel; and a manual operation member of the vehicle equipment.

According to this specific arrangement, the equipment element disposed adjacent to the step portion of the instrument panel is designed to be illuminated by the illumination member. This can increase the visibility of the equipment element.

In this vehicle interior illumination structure, when the equipment element disposed adjacent to the step portion is a lower manual operation element having a convex portion protruding from the step lower surface toward the vehicle interior, the vehicle interior illumination structure may be designed to allow at least the convex portion of the lower manual operation element to be hidden by the step upper surface when the driver sitting in the front seat visually recognizes the lower manual operation element reflected on the front windshield glass.

The “lower manual operation element” having the “convex portion” may include a manual operation member, such as buttons, dials and switches.

According to this specific arrangement, when the equipment element is a lower manual operation element having a convex portion protruding from the step lower surface toward the vehicle interior, the lower manual operation element can be effectively illuminated. In addition, when the driver sitting in the front seat visually recognizes the lower manual operation element reflected on the front windshield glass, at least the convex portion of the lower manual operation element is hidden by the step upper surface. This makes it possible to prevent at least the convex portion of the lower manual operation element illuminated by the illumination member from being reflected on the front windshield glass or side window glass distinctly in a light tone, for example, even during driving through a tunnel or at night, and keep the reflection from obstructing the driver's view.

Otherwise, when the equipment element disposed adjacent to the step portion is a lower manual operation element disposed on the step lower surface, the step lower surface may include an inclined zone which extends obliquely downward from the front edge thereof in the rearward direction and has the lower manual operation element disposed thereon, and the lower manual operation element may have a lighter tone than that of the step upper surface.

A specific example of the “lower manual operation element” may be the same as that described in connection with the aforementioned “lower manual operation element”.

According to this specific arrangement, the lower manual operation element has a lighter tone than that of the step upper surface. Thus, when the equipment element is a lower manual operation element disposed on the step lower surface, and the lower manual operation element is disposed on the inclined zone of the step lower surface extending obliquely downward from the front edge thereof in the rearward direction to provide enhanced operationality, the lower manual operation element is allowed to stand out against the indirect illumination with enhanced visibility. This structure also has an advantage of being able to obscure dusts attached on the lower manual operation element.

In the above vehicle interior illumination structure, when the instrument panel is formed with an upper pocket which is located above the step portion and concavedly curved in the frontward direction of the vehicle, the upper pocket may have a lower surface partly formed as a light-transmittable portion for transmitting illumination light from the illumination member therethrough.

According to this specific arrangement, the upper pocket located above the step portion of the instrument panel and concavedly curved in the frontward direction of the vehicle has a lower surface partly formed as a light-transmittable portion for transmitting illumination light from the illumination member therethrough. This allows illumination light from the illumination member to be transmitted to an inner space of the upper pocket through the light-transmittable portion, and effectively used for illuminating the inner space. Thus, user-friendliness in using the upper pocket can be enhanced without providing an additional illumination member.

Otherwise, when the instrument panel is formed with a lower pocket which is located below the step portion and concavedly curved in the frontward direction of the vehicle, the lower pocket may be designed to be illuminated by illumination light from the illumination member.

According to this specific arrangement, the lower pocket located below the step portion of the instrument panel and concavedly curved in the frontward direction of the vehicle is designed to be illuminated by illumination light from the illumination member. Thus, illumination light from the illumination member can be effectively used for illuminating the lower pocket, so that user-friendliness in using the lower pocket can be enhanced without providing an additional illumination member.

When the instrument panel further includes a lid portion for covering the upper or lower pocket in an openable and closable manner, the vehicle interior illumination structure may be designed to increase an intensity of illumination light from the illumination member in an open position of the lid portion as compared to that in a closed position of the lid portion.

According to this specific arrangement, the vehicle interior illumination structure is designed to increase an intensity of illumination light from the illumination member in an open position of the lid portion as compared to that in a closed position of the lid portion. Thus, when the lid portion is in the open position where it is necessary to illuminate an inner space of the pocket, the inner space can be more sufficiently illuminated. When the lid portion is in the closed position where it is unnecessary to illuminate the inner space of the pocket, the illumination light is adjusted to have a relatively low intensity so as to more effectively prevent the illumination light from obstructing the view of the driver sitting in the front seat. That is, an adverse affect on driving to be caused by illumination light getting into driver's eye can be more effectively avoided.

The above vehicle interior illumination structure where the vehicle has the side mirror disposed at the side of a vehicle body on the laterally outer side relative to the instrument panel may be designed such that respective projections of the lateral center and laterally outer edge of the illumination member and the side mirror which are viewed by an occupant sitting in a driver's seat (i.e. driver) are located approximately on a straight line in a plane orthogonal to the line of sight of the occupant viewing the laterally outer edge of the illumination member. As with the term “driver” in the vehicle interior illumination structure of the present invention, the “occupant sitting in a driver's seat (i.e. driver)” means an occupant who has an average physique of American male adults and sits in a driver's seat in a seated posture conforming to a so-called “hip point” to be uniquely set to each vehicle.

According to this specific arrangement, respective projections of the lateral center and laterally outer edge of the illumination member and the side mirror which are viewed by the driver are located approximately on a straight line in the plane orthogonal to the line of sight of the driver viewing the lateral outer edge of the illumination member. Thus, when the driver visually checks the side mirror on the outer side of the front passenger seat, he/she can more reliably view the side mirror on an extension line of a region of the instrument panel indirectly illuminated by the illumination member (i.e. the driver can move his/her line of sight from the lateral center toward the outer edge of the illumination member to visually find the door mirror on an extension line of the outer edge). This makes it possible to facilitate checking the position of the side mirror.

In this vehicle interior illumination structure, the illumination member may have a laterally outward portion with a lower luminance than that of a laterally inward portion thereof.

According to this specific arrangement, the laterally outward portion of the illumination member has a lower luminance than that of the laterally inward portion thereof. This makes it possible to more effectively avoid an adverse affect on driving to be caused by illumination light from the laterally outward portion which obstructs the driver's view as compared to that from the laterally inward portion.

The above vehicle interior illumination structure where the vehicle has the side mirror disposed at the side of a vehicle body on the laterally outer side relative to the instrument panel may be designed to allow a reflected image of a region of the instrument panel illuminated by the illumination member to be formed on the side window glass in such a manner that at least a part of the reflected image overlaps the side mirror.

According to this specific arrangement, even through a reflected image of a region of the instrument panel illuminated by the illumination member is formed on the side window glass in such a manner that at least a part of the reflected image overlaps the side mirror, the illumination member designed to perform indirect illumination can effectively prevent the occurrence of the problem that a target region illuminated by the illumination member distinctively stands out more than the side mirror when the driver visually checks the side mirror, to obstruct the driver's view toward the side mirror.

As mentioned above, the vehicle interior illumination structure of the present invention which comprises, in combination, the instrument panel installed in a front interior area of a vehicle and the light-guiding illumination member disposed in the instrument panel, makes it possible to prevent illumination light of the illumination member from obstructing the view of a driver sitting in a front seat in the vehicle interior.

This application is based on Japanese Patent Application Serial Nos. 2004-235930, 2004-235931, and 2005-162751, filed on Aug. 13, 2004, Aug. 13, 2004, and Jun. 2, 2005, respectively, the contents of which are hereby incorporated by reference.