受験番号：22IPE008

問１[Claim 1]
An optical sensor, comprising:a light-emitting part that externally emits, on the basis of a pulse signal, pulselight;
a light-receiving part that generates a photo-electric current corresponding toan intensity of externally incident light;
a current-voltage conversion circuit that converts the photo-electric current
into a voltage signal;a high-pass filter that extracts, from the voltage signal, an AC component
having at least a predetermined frequency and outputs the extracted AC component asfiltered output indicating a signal waveform around a reference voltage;a polarity inverting amplifier, in which on the basis of the pulse signal, anon-inverting amplifier state and an inverting amplifier state are switched, which
outputs the filtered output in the non-inverting amplifier state, where the filter output
is not inverted, and which outputs the filter output in the inverting amplifier state,
where the filtered output is inverted relative to the reference voltage; andan integrator that integrates, on the basis of the reference voltage, the outputof the polarity inverting amplifier.
[Claim 2]
The optical sensor according to claim 1, further comprising a delay circuit thatdelays the pulse signal to be outputted to the polarity inverting amplifier.
問２
A game system is known which generates an image seen from a given
viewpoint in an object space which is a virtual three-dimensional space, and such agame system is popular because a user is capable of experiencing a so-called virtualreality. For example, in a role-playing game, a player operates a character (object)
allowing for movement on a map in an object space. The player enjoys the game when
the character is made to fight with an enemy character, to talk with another character,and to visit various towns, for example.
In such a game system, an object that represents a character and the like isusually configured by a plurality of polygons. The object configured by the polygons isarranged in an object space. When a so-called geometry process is applied, an image
seen from a virtual camera is generated. As a result, even when the object is viewed
from various directions by the virtual camera, it is possible to generate a consistent
game image.
There is, however, a problem that although thus-generated game image is amathematically correct image, a player is somewhat not emotionally attracted. For
example, when a character appearing in an animation film, a comic book or the like isexpressed by an object, if shading is applied to the object by Gouraud shading, forexample, then it is possible to obtain a real image; however, an image is generated
which exhibits a different look and feel from a viewer is used to from the animation film,
the comic book, or the like.
問３
As illustrated in Fig. 4, when a motion sensor 25 installed together with alighting equipment 20 at an outdoor side of an entrance door senses a human body 30, alighting lamp of the lighting equipment 20 is first lit up. When the lighting lamp of thelighting equipment 20 is lit up, a current flowing through the lighting equipment 20 isdetected by a current detection circuit 14 (Fig. 3).
A control unit 200 lights up a lighting lamp of a lighting equipment 10,
triggered by a current detection signal output from the current detection circuit 14, forexample, on the basis of previously set setting condition information, after an elapse of apredetermined light-up interval time period since the lighting lamp of the lighting
equipment 20 is lit up. As a result, when the lighting system 100 is used, if the humanbody 30 is a suspicious person, for example, then it is possible to create a make-believe
situation where there is an occupant indoors, and thus, it is possible to use the system
100 for preventing a crime or the like.
A controller 15 controls an LED circuit 17, for example, to light up an LED so
as to inform a lighting state of the lighting lamp of the lighting equipment 20, inresponse to a current detection signal from the current detection circuit 14, and also
brings a switch part 19 into an ON state after an elapse of a previously set light-up
interval time period t1 since the lighting lamp of the lighting equipment 20 is lit up.
When the switch part 19 is brought into the ON state, a current flows through anelectric lamp line at the lighting equipment 10 side, and the lighting lamp of thelighting equipment 10 is lit up, resulting in a lit-up state.