Incremental printing of symbolic information – Light or beam marking apparatus or processes – Scan of light
Reexamination Certificate
1999-03-12
2001-11-27
Pham, Hai C. (Department: 2861)
Incremental printing of symbolic information
Light or beam marking apparatus or processes
Scan of light
C257S713000, C257S719000
Reexamination Certificate
active
06323891
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an imaging apparatus and, more particularly, it relates to an imaging apparatus adapted to be suitably used for the image input section of a digital copying machine, a scanner, a medical image input equipment or a non-destructive tester.
2. Related Background Art
An imaging apparatus of the type under consideration may typically be used for the image input section of medical or non-destructive inspection equipment. Such equipment may be designed to irradiate an object of inspection with radioactive rays such as X-rays or &ggr;-rays, convert the wavelength of the rays transmitted through the object of inspection into the photosensitive wavelength range of the photodetecting section of the equipment by means of a wavelength changer such as a fluorescent plate and then convert the detected rays into electric signals in the photodetector to produce electric information on the object of inspection.
FIG. 1
of the accompanying drawings schematically illustrates a known imaging apparatus of the above described type.
Referring to
FIG. 1
, it comprises a fluorescent plate
1
, photoelectric transfer elements
2
a
for converting visible light into electric signals, sensor substrates
2
b
, spacers
3
a
, TAB films
5
a
operating as flexible circuit substrates, a moisture-proof film
6
, a base
7
, an apparatus cabinet
8
, a frame member
8
a
, a covering member (grid)
8
b
, a bottom member
8
c
, an adhesive layer
9
, ICs
10
a
(for reading signals), radiator sheets
10
c
, circuit substrates
15
, radiator fins
16
and spacers
17
. Arrow
201
in
FIG. 1
indicates the direction along which a load is normally applied to (or radioactive rays strike) the apparatus.
As seen from
FIG. 1
, an imaging apparatus of the type under consideration is based on combining photoelectric transfer elements
2
a
and a fluorescent plate
1
. The photoelectric transfer elements
2
a
typically comprises amorphous silicon film (hereinafter referred to as a-Si film) as photoelectric conversion layer because it can be formed with ease on a sensor substrate
2
b
that may be a glass substrate having a large surface area and it can be used not only for photoelectric transfer elements
2
a
but also as semiconductor material for preparing switch TFTs that operate as switching devices. A-Si film is popularly used as semiconductor material for preparing photoelectric transfer elements
2
a
because both photoelectric transfer elements
2
a
and their respective switch TFTs (not shown) can be formed on a glass substrate
2
b
in a same single process by using it as semiconductor material.
A glass substrate is popularly used for each of the substrates (sensor substrates)
2
b
carrying photoelectric transfer elements
2
a
because they are required to be free from chemical reactions with the semiconductor devices of the apparatus, resist the high temperature of the semiconductor forming process and maintain dimensional stability. The fluorescent plate
1
is prepared by applying a fluorescent material of a metal compound to a resin plate. The gap separating the fluorescent plate
1
and the photoelectric transfer elements
2
a
has to be held to a sufficiently small value (typically less than tens of several &mgr;m) relative to the size of the pixels (more than a hundred &mgr;m) of the photoelectric transfer elements
2
a
and, in most cases, the fluorescent plate
1
and the substrates
2
b
are bonded together by means of an adhesive agent.
When the photoelectric transfer elements
2
a
are, or the fluorescent plate
1
is, required to be moisture-impermeable, both the fluorescent plate
1
and the photoelectric transfer elements
2
a
may be wrapped and hermetically sealed by a moisture-impermeable and X-ray transmissive film (e.g., evaporated Al film)
6
. Then, the drive circuit substrate
15
for driving the photoelectric transfer elements
2
a
and reading data therefrom is fitted to the rear surface of the sensor substrates
2
b
carrying the photoelectric transfer elements
2
a
thereon with spacers
17
interposed therebetween and subsequently semiconductor circuit devices (electronic components)
5
c
for driving the converters are mounted thereon. Then, the substrates
2
b
are rigidly secured to the surface of the base
7
by means of an adhesive layer
9
. Thereafter, the base
7
is fitted to the bottom plate
8
c
of the apparatus cabinet
8
with spacers
3
a
interposed therebetween, the bottom plate
8
c
being adapted to operate as holder for the above listed components.
Such imaging apparatus are conventionally used for X-ray photography as stationary apparatus. However, in recent years, there is an increasing demand for lightweight, compact and portable imaging apparatus adapted to rapid imaging operations for producing fine images.
Additionally, imaging apparatus having the above described configuration are required to safeguard the substrate
2
b
and other related components against impacts that can be applied thereto during transportation and the apparatus are also required to be safeguarded as a whole against deformation, e.g, that of the closure
8
b
of the apparatus cabinet
8
, that can be caused by the external load
201
(mainly the weight of the person to be photographed) of the apparatus during X-ray photographing operations.
Meanwhile, the use of heat-radiating members such as radiator fins
16
for releasing heat from the ICs (integrated circuit devices)
10
a
including signal reading ICs and driver ICs arranged on the flexible circuit substrate
5
a
has been proposed. Additionally, the use of a specifically prepared member has been proposed in order to shield the drive circuit and the ICs from X-rays and other radioactive rays because radioactive rays irradiated onto the apparatus can give rise to operation errors on the part of the semiconductor circuit devices (electronic components)
5
c
arranged on the drive circuit substrate
15
and the drive circuit including the drive ICs
10
a
arranged on the flexible circuit substrate
5
a
and even destruct the semiconductor circuit devices
5
c
. For example, a lead plate may be used to completely cover the base in order to make the apparatus free from troubles attributable radioactive rays. Obviously, however, such an arrangement is against the attempt for producing a down-sized and lightweight imaging apparatus.
Therefore, there is a problem how a down-sized, lightweight and portable imaging apparatus can be realized by taking the requirement of safeguarding the sensor substrates
2
b
against impacts that can be applied to them during transportation and that of preventing the apparatus cabinet from being deformed by the load applied to the apparatus during the operation of X-ray photographing to adversely affect the performance of the photoelectric transfer elements into due consideration.
In the case of the above described conventional apparatus, the base
7
for holding the sensor substrates
2
b
carrying thereon photoelectric transfer elements
2
a
, the bottom plate
8
c
of the apparatus cabinet
8
rigidly securing the base
7
, the frame member
8
a
of the apparatus cabinet
8
arranged around the above listed components, the heat-radiating members
16
of the drive ICs
10
a
and the lead plate (not shown) for shielding the apparatus against radioactive rays including X-rays are all heavy and bulky and hence operate against the attempt for realizing a lightweight imaging apparatus. Additionally, the drive ICs, the signal reading ICs in particular, have to be provided with respective heat-radiating members on a one-to-one basis in order to ensure stable temperature-related characteristics required for reading analog signals correctly. However, such an arrangement inevitably increase the number of components to operate against the attempt for realizing a down-sized imaging apparatus.
FIG. 2
of the accompanying drawings is a schematic cross sectional view of another known imaging apparatus realized in the form of a cassette. T
Kajiwara Kenji
Kitani Masashi
Shimamura Yoshinori
Canon Kabushiki Kaisha
Fitzpatrick ,Cella, Harper & Scinto
Pham Hai C.
LandOfFree
Imaging apparatus with thermal discharger for transferring... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Imaging apparatus with thermal discharger for transferring..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Imaging apparatus with thermal discharger for transferring... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2605672